To get the volume of the cylinder you'll need your formula, which is:
Volume = radius^2 • π • height
So we are trying to find the volume of the water in the cylinder, not the whole cylinder itself.
Let's find the radius. Our radius is half of the diameter, which in this case is 1, because 2 / 2 = 1
Now we need to find the height. So we need to find what 3/4 of 4 is.
If 1/4 of 4 is 1, then 3/4 of 4 equates to 3.
So our equation is:
Volume = 1^2 • π • 3
Volume = 9.42 (if you are rounding to the nearest hundredth.)