plz use Java

Lab#2 1) Write a program that calculates the area of a donut (i.e., there is a big circle with a small circle inside it, calculate the area that is taken up by the space between these two circles). Write a method areaCircle() which returns the area of a circle. 2) Write a program that computes the distance (c) between two points (a and b). Write your own method called square that takes a number of type double as an argument and returns the square of that number. Following is the way to calculate the straight line distance between two points: Square root of both points: c= V(XA XB)2 + (YA YB)? 3) Write a program that prints out the face of a die in random (i.e., a random number between 1 and 6)