Identify whether the graph displays a linear or nonlinear functio

The length of the line segment ac is 8x-9 what is the value of x

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.

The distance from the sun to earth is about 1.5×10 to the 11th m suppose light travels at a speed of 3×10 to the 8th m per second about how long does it take light from sun to reach earth