Plz help me I have to pass this

Simplify the expression 8h - 57-3m by adding or subtracting the like term

The manager at gabriela's furniture store is trying to figure out how much to charge for a book shelf that just arrived. the book shelf was bought at a wholesale price of $ 1 4 7 . 0 0 $147.00, and gabriela's furniture store marks up all furniture by 6 0 % 60%. at what price should the manager sell the book shelf?

The path traveled by a bottlenose dolphin as it jumps out of water is modeled by the equation y=-0.4+3x, where t is the height above water and x is the horizontal distance in feet. if a beam of light is shone upward at an angle modeled by the equation x+y=10, at what height from the waters surface will the beam of light hit the dolphin