28. What is the input for the "perspective" function? What does it do? Sketch and example. (This is tricky - don't forget the normalization.) 29. Sketch the cosine function from to . Label the sketch with the key defining elements. What is the maximum value of the cosine function? 30. Suppose a parametric equation of a sphere is given as x(r,,)=rcos()sin()sin()sin()cos() If r=2,=/2, and 02, what geometric shape does this equation generate? 31. What is the action of the following maps? 28. What is the input for the "perspective" function? What does it do? Sketch and example. (This is tricky - don't forget the normalization.) 29. Sketch the cosine function from to . Label the sketch with the key defining elements. What is the maximum value of the cosine function? 30. Suppose a parametric equation of a sphere is given as x(r,,)=rcos()sin()sin()sin()cos() If r=2,=/2, and 02, what geometric shape does this equation generate? 31. What is the action of the following maps