Help me with this question please

Cal's go cart has a gas tank with the dimensions shown below. he uses a gas can that holds 11 gallon of gas, to fill the go cart tank. 11 gallon = 231 inches^3 how many full gas cans will it take to fill the go cart's gas tank?

Let f(x) = 5/x and g(x)=2x2+5x. what two numbers are not in the domain of f o g

In the diagram, ab is tangent to c, ab = 4 inches, and ad = 2 inches. find the radius of the circle.