Worksheet # 2. Size 1 1. An arch is in the form of a semiellipse that has a span of 250 ft and with the greatest height of 50 ft. There are two vertical supports equidistant from each other, and 25 ft from the minor axis. Find the height at the support. 2. The arch of an underpass is a semi-ellipse 60 ft wide and 20 ft high. Find the clearance at the edge of a lane if the edge is 20 ft from the middle. 3. An arched entrance to a zoo has a cross section, with the curve a semi-ellipse. a. Find the heights of arch measured from the ground at every 3 ft distance from the point P. b. If it is 10 ft thick, find the number of cubic yards of concrete required for its construction. The area of an ellipse of semi-axes a and b given by πab 4. The arch of an underpass is a semi-ellipse 60 ft wide and 20ft high arched entrance to a zoo has a cross section, with the curve a semi-ellipse. a. Find the heights of arch measured from the ground at every 3 ft distance from the point P. ft high. Find the clearance at the edge of a lane if the edge is 20 ft from the middle. b. If it is 10 ft thick, find the number of cubic yards of concrete required for its construction. The area of an ellipse of semi-axes a and b given by πab.