F(5) = ? It is not 5 as I tried at, and not f5

Two friends are reading books. jimmy reads a book with 21,356 words. his friend bob reads a book with one-and-a-half times as many words. which expression represents the number of words bob reads?

What is the length of ac in the given triangle?

The volume of a rectangular prism is found by multiplying the length, width, and height of the prism. a rectangular prism has a width of 5x^2units, a length of 7x^3 units and a height of 2x^4 units. which is the volume of the prism in terms of x?