Can a mathematician assist?

explain how (2*10^-3)^3 = 8e^-9

i understand how the exponent is -9 but how does the 2 become an 8

Astore has apples on sale for three dollars or 2 pounds how many pounds of apples can you buy for nine dollars if an apple is approximately 5 ounces how many apples can you buy for nine dollars

What is the inverse of the function f(x) = 2x + 1?

Tamar is measuring the sides and angles of tuv to determine whether it is congruent to the triangle below. which pair of measurements would eliminate the possibility that the triangles are congruent