Write a java program that prompts the user for the diameter of a circle and an x-increment "dx" (both in centimeters), then calculates and displays the area of the circle in square centimeters using a Riemann Sum. To find the area of the circle using a Riemann sum, first, find the area of one quadrant by dividing the quadrant into rectangles, each of width "dx" (as in "delta-x", which means "change in x"), and then use the Pythagorean Theorem to find the "y" value at each "x" value.
y = sqrt(r^2 - x^2)
Multiply "dx" by "y" to get the area of the rectangle at that "x" value (see attached diagram). Add the areas of the rectangles together, and you have the area of the quadrant. To obtain the area of the entire circle, multiply the quadrant's area by four.

The program should use a for loop to do the calculations.
All variables should be of type double.
It should also use at least 2 methods.