A. calculate the volume of the solid of revolution created by rotating the curve y = 3 + 3 exp(-5 x) about the x-axis, for x between 2 and 4. volume : 56.55 b. the equation of a circle of radius r, centered at the origin (0,0), is given by r^2 = x^2 + y^2 rearrange this equation to find a formula for y in terms of x and r. (take the positive root.) what solid of revolution is swept out if this curve is rotated around the x axis, and x is allowed to vary between -r and r suppose we wanted to set the following integral so that v gives the volume of a sphere of radius r v = integral a to b f(x) dx what would a, b and f(x) be? a=b=f(x)=carry out the integration, and calculate the value of v in terms of r. v=