Which inequality represents all of the possible values of x?

In simplified exponential notation, the expression a^2•a^-3•a 1/a 0

How do i start to solve? would appreciate a walk-thru! a bird sitting 16ft above the ground in an apple tree dislodges an apple. after how many seconds does the apple land on the ground? (assuming that no branches will interfere with it's fall)

What is the measure of angle a and angle c ?