Problem: a full stationary oil tank that is a right circular cylinder has a radius of 100 feet and a height of 25 feet . oil is pumped from the stationary tank to an oil truck that has a tank that is a right circular cylinder until the truck ' s tank is completely filled . if the truck ' s tank has a radius of 5 feet and a height of 10 feet , how far did the oil level drop in the stationary tank ? 
Options: ['a ) 2.5 ft', 'b ) 1 ft', 'c ) 0.5 ft', 'd ) 0.25 ft', 'e ) 0.025 ft']
e