Hello I need help with the following: 27,28,30

27 Find the area bounded by: f(x) = cos(x) +3, g(x) = cos(2r) +1, r= x, and r = 3x 28 Find the volume of the solid generated by revolving /(x) = 4- 4-r| about the r-axis on [0, 8). 29 Find the volume of the solid generated by revolving f(x) = \\ R2 - x about the y-axis on [0, R]. 30 Find the arc length of the astroid, ?/3 + 23 = 2, on 1,2V/2 . What is the entire arc length