Given:
1st tank: conical with diameter of 10 feet and height of 15 feet.
2nd tank: hemisphere with a radius of 5.5 feet
volume of a cone = πr² h/3
V = 3.14 * (5ft)² * 15ft/3
V = 3.14 * 25ft² * 5ft
V = 392.5 ft³
392.5 ft³ * 7.48 gallons/ft³ = 2,935.9 gallons
volume of a hemisphere = (2πr³)/3
V = [2 * 3.14 * (5.5ft)³]/3
V = (2 * 3.14 * 166.375 ft³)/3
V = 1,044.835 ft³/3
V = 348.28 ft³
348.28 ft³ * 7.48 gallons/ft³ = 2,605.13 gallons