Confused if someone could show the answer and steps!

An astronaut drops a rock into a crater on the moon. the distance, d(t), in meters, the rock travels after t seconds can be modeled by the function d(t)0.82. what is the average speed, in meters per second, of the rock between 5 and 10 seconds after it was dropped?

Apublic library wants to place 4 magazines and 9 books on each display shelf. the expression 4s+9s represents the total number of items that will be displayed on s shelves. simplify the expression

Solve this system of equations. 12x − 18y = 27 4x − 6y = 10