Ineed i don't understand this at all me

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?

What are the solutions of the system? solve by graphing. y = -x^2 -6x - 7 y = 2

Write the equation in logarithmic form 8^x=64