E. Solve the following problems completely:

1. A cable hangs in a parabolic are between two columns 100 feet (ft.) apart. The columns are 40 ft. high and the lowest point on the suspended cable is 10 ft. above the ground.
2. Find the equation of the arc if the vertex is the lowest point of the cable.

1. Find the height of the cable from the ground at a point 30 ft. from the lowest point of the cable.

1. The cables of a horizontal suspension bridge are supported from two towers 40 ft. high and 150 ft. apart. If the bridge is tangent to the cables at its center, find the length of one of its vertical support 30 ft. from one of the towers.