20. the product of 2 times a and 5 times b
Algebraic expression

Describe all the numbers that when rounded to the nearest thousand are 645,000

Afamily went out to dinner and their bill was $113.if they want to leave a 19% tip, how much should they leave.

Describe how to determine the average rate of change between x = 4 and x = 6 for the function f(x) = 2x^3 + 4. include the average rate of change in your answer.