80. Let A be the region bounded by the lines y=0.5x and y=2-0.5x between 0 less than or equal to x less than or equal to 2. (0<= x <= 2)

a. Set up, but do not evaluate, the definite integral that gives the volume of the solid formed by rotating region A around the x-axis

b. Set up, but do not evaluate, the definite integral that gives the volume of the solid formed by rotating region A around the line y=4

c. Set up, but do not evaluate, the definite integral(s) that give(s) the volume of the solid formed by rotating region A around the y-axis. (hint: split it into two)

d. Suppose region A is the base of a solid whose cross-sections perpendicular to the x axis are semi circles. Set up, but do not evaluate, the definite integral that gives the volume of this solid.

I am clueless of what to do here. Please guide me through this Thanks.