0.4(20-10m)+ 2.5-2m-12.5 the answer is -6 -2 but i need the explaination

Karianne and lucius are analyzing a linear function on a graph. karianne says that unit rate is equal to rate of change, but that slope is calculated differently. lucius says that unit rate, rate of change, and slope are calculated the same way. who is correct? explain your answer.

The weekly revenue for a company is r = 3p^2 + 60p + 1060, where p is the price of the company's product. what price will result in a revenue of $1200.

What is x3+3x2−16x−48 divided by x−1?