storage tank negligible mass and 30m high filled gasoline please calculate following gauge p

a storage tank of negligible mass and 30m high is filled with gasoline. please calculate the following: the gauge pressure and absolute pressure at the bottom of the tank. the force that acts on a square access hatch at the bottom of the tank that measures 0.5m x 0.5m. given that tha tank is shaped light a right circular cylinder with a height of 30m and with a base radius of 10m. the tank is attached to a steel cable of neglible mass and immersed in water. calculate the tension in the cable before and after it is immersed in water.