Find the surface area of the portion of the hemisphere z = (25 - x2 - y2)1/2 that lies above the region R bounded by the circle x2 + y2 = 9.

Sketch the solid that results when the given circle of radius length 1 unit is revolved about the horizontal line that lies 1 unit below the center of that circle.

Does the sphere x2+y2+z2=100 have symmetry with respect to the a x-axis? b xy-plane?

Use the analytic method to decide what type of triangle is formed when the midpoints of the sides of an isosceles triangle are joined by line segments.