Hi please help 1. what is the rate of change from year 2 to year 7?

2. during which interval is the rate of change the greatest?
A. year 0 to year 2
B. year 2 to year 7
C. year 7 to year 9
D. year 9 to year 13

Problem number 26 of the rhind papyrus says: find a quantity such that when it is added to of itself the result is a 15. the modern day equation that models this problem is x + x = 15. what is the solution to the equation? x = 10 x = 12 x = 15 x = 30