15. The instantaneous rate of change is determined by finding the difference quotient over a very small interval. 16. A limit exists if both the right-hand and left-hand limits are equal. 17. A jump discontinuity occurs when a function jumps over the x-axis. 18. JA vertical asymptote can be found by solving the numerator equal to zero in a rational function. 19. A piecewise function always has a jump discontinuity. 20. Functions that have an indeterminate form when evaluating a limit can always be simplified by factoring