Fill the validateForm function to check that the phone number contains a number (use the isNaN function) and that the user name is less than 11 characters long. Display "Phone number is invalid" and/or "User name is invalid" in the console log if the check does not pass. Use the preventDefault function to avoid submitting the form when the inputs are invalid.
html code:

Username:

JAVA:

var form = document. getElementById("userForm");

function validateForm(event) {
var phoneNumber = form. phoneNumber. value;
var userName = form. userName. value;

/* Your solution goes here */

}

form. addEventListener("submit", validateForm);

Write a program that uses a random number generator to generate a two digit positive integer and allows the user to perform one or more of the following operations: a. double the number. b. reverse the digits of the number. c. raise the number to the power of 2, 3, or 4. d. sum the digits of the number. e. if the number is a two-digit number, then raise the first digit to the power of the second digit. f. if the number is a three-digit number and the last digit is less than or equal to 4, then raise the first two digits to the power of the last digit. after performing an operation if the number is less than 10, add 10 to the number. also, after each operation determine if the number is prime. each successive operation should be performed on the number generated by the last operation. your program should not contain any global variables and each of these operations must be implemented by a separate function. also, your program should be menu driven. 7. (fraction calculator) write a program that