The base of a solid is a circle with radius 7. The cross-sections of the solid perpendicular to afixed diameter of the base are squares. If the circle is centered at the origin and the cross-sections are perpendicular to the x-axis, findthe areaA(x) of the cross section atx.

White shapes and black shapes are used in a game. some of the shapes are circles. while the rest are squares. the ratio of the number of white shapes to the number of black shapes is 5: 11. the ratio of the number of white cicrles to the number of white squares is 3: 7. the ratio of the number of black circles to the number of black squres is 3: 8. work out what fraction of all the shapes are circles.