filter method to filter an array in JavaScript

Задание 1

Given an array of numbers. Leave only positive numbers in it.

Задание 2

Given an array of numbers. Leave only negative numbers in it.

Задание 3

Given an array of numbers. Leave in it only numbers that are greater than zero, but less than 10.

Задание 4

Given an array with strings. Leave in it only those strings whose length is more than 5 characters.

Задание 5

Given an array of numbers. Leave in it only those numbers whose product of their values and index numbers is less than 30.

Задание 6

An array is given, it can contain ordinary elements and subarrays, for example [1, 2, [3, 4], 5, [6, 7]]. Leave only ordinary elements in it.