Program all 3 please !

Below is a sample Java program that reads a number from the keyboard and then displays it on the screen. Use this template to write the following programs /* Example program showing simple input and output. */ public class TestExp { public static void main (String[] args) { /*Create a Scanner object to read data from the keyboard */ java util Scanner keyboard = new java util. Scanner (System.middotin): double myVar: //declare input variable System.out.println("Enter a number") //display prompt myvar = keyboard. nextDouble (): //get a number from the keyboard System.out.println ("The number is "+myVar): //display the number } } Write a program that converts liters to gallons. There are 3.78541 liters in a gallon. Input the number of liters and display the number of gallons. Example: For an input of 10.0 liters, the answer is 2.6417217685798895 gallons. Write a program that calculates the amount of latex required to make a balloon of a given diameter. Assume the balloon walls are 0.25 millimeters in thickness when inflated. The program inputs the diameter of the balloon in centimeters and displays the amount of latex is cubic centimeters using the equation: latex = 0.025 pi 4 (diameter/2)2 Example: A 30.0 cm diameter balloon will require 70.68583470577035 cc of latex Write a program that reads in the length of an edge of a tetrahedron and displays its volume, which can be computed from the equation: volume = edge^3/6 Squareroot 2 Example: For a tetrahedron whose edge is 4.0, the area is 7.542472332656506