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Given a sentence, split it into an array of words using the String.prototype.split() method.

Create a function that takes a string and a number, and repeats the string the given number of times.

Create a function that takes in a string and checks if it starts with a given substring. Return a boolean indicating whether or not the string starts with the given substring.

Create a function that normalizes a string using String.prototype.normalize method.

Write a function that finds the last index of a given element in an array using the Array.prototype.findLastIndex method.

Implement a function that concatenates a given string 'n' times using the String.prototype.repeat() method.

Write a function that takes a string and regular expression as inputs, and returns an array of all matches found using the String.matchAll() method.

Create a function that replaces all occurrences of a substring with a new string.

Write a function that uses recursion to calculate the factorial of a given positive integer.

In this kata, you will be working with the String.prototype.toLocaleUpperCase() method to convert a string to uppercase according to the user's locale.

Write a function that returns the value of a given string using the String.prototype.valueOf() method.

Create a function that returns the current date as a number (1-31).

Create a function that takes a string as input and returns the same string in uppercase letters using the `toString()` method of the String object.

Create a function that uses Array.prototype.findLast() to find the last element in an array that matches a given condition. Return the element if it exists or null if it does not.

Write a function that joins two arrays into a single string using Array.prototype.join() method.

Write a JavaScript function to find the index of an item in an array using Array.prototype.findIndex().

Write a function that takes a date object and a number representing the desired month, and sets the month of the date to the given month.

Create a function that takes a string and a number as arguments, and pads the string on the right side with spaces until the string reaches the desired length.

Create a function that takes an array of numbers and returns the index of a given element. Use Array.prototype.findIndex() to implement the function.

Implement a function that takes a string as input and returns it in lower case.

Write a function that concatenates two strings using the String.prototype.concat() method.

Write a function that takes an array and a value as arguments and returns the index of the last occurrence of that value in the array using Array.prototype.lastIndexOf(). If the value is not found, return -1.

Create a function that takes in two parameters, a string and a substring, and checks if the string includes the substring. Return a boolean value.

Implement a function that removes all unused items in a Set collection

Given two arrays, join them to create a new array.

Write a function that checks whether a given string ends with the specified suffix or not.

Implement a function that groups the elements of an array based on a given predicate function.

Create a function that removes white space at the end of a given string using String.prototype.trimEnd().

Write a function that checks if a given variable is an array. If it is an array, return true, otherwise return false.

Create a function that will return an array in a localized way using the toLocaleString method.

Create a function that returns an array of values of an array using the Array.prototype.values() method.

Create a function that concatenates two strings using the String.prototype.concat() method.

Create a function that takes a date and a year as arguments and returns a new date with the year set to the specified value using Date.prototype.setFullYear().

Implement a function that removes leading and trailing whitespace from a string using the String.prototype.trim() method.

Use Array.prototype.slice() to solve the following tasks.

Create a function that takes two parameters: a string and a target substring, and returns the index of the first occurrence of the target substring in the string. If the target substring is not found, return -1.

Create a function that concatenates two strings using the String.prototype.concat() method. The function should take two string parameters and return the concatenated string.

Create a function that determines if two strings are anagrams of each other.

Create a function that takes a year (YYYY) and returns the date object with its year set to the provided year.

Write a function that accepts a date object and a number of seconds (0 - 59) and returns a new date object with the seconds set to the provided value. The operation should be done using the setUTCSeconds() method.

Write a function that converts a given string to uppercase

Create a function that receives a string and a regular expression pattern and returns an array of all the occurrences of the pattern in the string using String.prototype.matchAll().

Write a function that accepts a string and a number as arguments, then returns the character at that position in the string. Use String.prototype.charAt() for this exercise.

Implement a function that groups an array of objects by a given key and returns a new array of objects, where each object has a key and an array of objects that have that key.

Given a date, return the UTC date.

Given an array of numbers and a start index, remove a certain number of elements from the array and replace them with new elements.

Write a function that takes a string and a search term and returns the index of the first occurrence of the search term in the given string. If the search term is not present in the string, return -1.

Write a function that returns a substring of a given string, starting at a specified index and ending before a specified index.

Create a Stock Advisor that recommends which stocks to buy based on certain parameters.

Write a function that flattens nested arrays using Array.prototype.flat() method.

Create a function that takes an array and reverse its order in place.

Create a function that receives a string and a number as parameters. The function should return the string repeated `n` times, where n is the number passed as parameter.

Write a function that takes a string and a substring, and returns the index of the first occurrence of the substring in the string. If the substring is not found in the string, return -1.

Write a function that takes a string as input and splits it into an array of words using String.prototype.split(). Then, join the array back into a string using Array.prototype.join(). Finally, return the new string with a different delimiter separating each word.

Write a function that takes in a string and a target substring, and returns the index at which the target substring is first found. If the target substring is not found in the string, return -1. Use the built-in JavaScript method `indexOf()` to solve the problem.

Create a function that takes in an array of music tracks and returns an object with the count of each genre in the array

Create a function that sorts an array of strings in alphabetical order using String.prototype.localeCompare()

Create a function that uses the String.prototype.lastIndexOf() method to find the index of the last occurrence of a specified substring in a given string.

Create a function that takes in a string and uses String.prototype.match() to find all occurrences of a pattern within the string.

Implement normalize method to format a string removing all the accents

Given an array of objects, group the objects based on a specific key and return a map object.

Write a function that takes a string and removes any trailing whitespace at the end of it using String.prototype.trimEnd().

Complete the functions provided to properly utilize the Date.now() method.

Implement a function that uses String's padStart method to add leading zeros to a number string to ensure it always has a minimum length

Create a function that replaces all instances of a given substring with another string within a larger string using String.prototype.replaceAll() method.

Create a function that takes a start time and an event duration and returns the end time of the event, using the Date.prototype.setHours() method to set the hours of the start time.

Write a function that takes a date string as input and converts it to a UTC date string format.

Create a function that receives a Date object and returns the milliseconds that have elapsed since the start of the day.

Create a function that receives a string and normalizes it using the String.prototype.normalize() method. Apply the NFC normalization form.

Write a function that checks if a given string includes a specific substring. Use String.prototype.includes() method.

Implement a function that sets the milliseconds of a given date object to a specified value.

Create a function that takes an array and removes a portion of the array, as specified by the arguments, and returns the removed portion.

Write a function that returns the result of a string match with a given pattern.

Write a function that returns the index of the first occurrence of a given element in an array using Array.prototype.indexOf(). If the element is not found in the array, return -1.

Write a function that takes two arrays as arguments and concatenates them into a new array using the Array.prototype.concat() method.

Write a function that takes a Set object as a parameter and returns an array of keys using Set.prototype.keys().

Create a function that uses Array.prototype.entries() to iterate over an array and perform some operations.

Write a function that uses the Date.prototype.getDay() method to determine the day of the week for a given date object.

Write a function that takes an array of numbers and returns their sum, using Array.prototype.reduceRight().

Implement a function that takes a Date object as input and returns a formatted string

Converts a given date to a time string

Create a function that takes in a string and a length and returns a new string with the original string padded with leading spaces if it is shorter than the provided length.

Write a function that normalizes a string using String.prototype.normalize().

Write a function that takes a string and a substring as arguments, and finds the last occurrence of the substring in the string. If the substring is not found, return -1.

Create a function that slices a string based on a given start and end indexes

Write a function that takes in a date and returns the seconds within the minute in UTC time.

Write a function that takes an array and a value and pushes the value to the end of the array using Array.prototype.push().

Convert a string to an array of Unicode code points using String.prototype.codePointAt() method.

Complete the functions to find the index of an element in an array using Array.prototype.indexOf().

Write a function that takes a string and returns an array of code points for each character in the string using String.prototype.codePointAt() method.

Write a function that takes in a string and uses precision cutting to remove all occurrences of the letter 'e'. Return the resulting string.

Create an Inventory Management System that allows users to add, remove and update items in the inventory.

Create a function that repeats a given string n times.

Create a function that takes a string and returns a new string that is a slice of the original string. The function should take two arguments, start and end, which represent the starting and ending indices of the slice.

Write a function that can take in a list of numbers and precision cut them to a desired number of decimal places.

Create a function to search for a substring in a given string using String.prototype.search() method.

Write a function that takes a Date object and returns a string representing the time portion of the date in the current time zone using the toLocaleTimeString() method. The function should also take an optional argument specifying the locale to use.

Create a function that returns the current year using Date's built-in getFullYear method

Write a function that checks if a given string has a unicode character code point greater than or equal to 128. Use the String.prototype.codePointAt() method.

Replace all vowels in a string with a '-'.