Please use as many details as possible when explaining and please answer both.​

What is the common difference in the following arithmetic sequence? 7,3,-1,-5

Determine the volume of a cylinder bucket if the diameter is 8.5 in. and the height is 11.5 in.

Adj has a total of 1075 dance and rock songs on her system. the dance selection is 4 times the size of the rock selection. write a system of equations to represent the situation.