The diagram below shows a cross-section of a metal pipe, that has a length of 50 cm. The inner diameter of the pipe is 20 cm. The outer diameter of the pipe is 30 cm.

Calculate the volume of metal needed to make the pipe.

Grading scale 1 has the following weights- (tests- 50% quiz- 25% homework- 15% final exam- 10%). calculate your final average if your performance in the class is as follows-test grades- {88, 84, 90, 75, 70, 81); quiz grades- {88, 67, 90, 90, 45, 99, 76, 98, 100}; homework- 90; final exam- 75