Which of the following statements is false? (5 points) select one: a. the sum of two rational numbers is always rational. b. the product of a nonzero rational number and an irrational number is always irrational. c. the product of two rational numbers is always rational. d. the sum of two irrational numbers is always rational.

The average number of vehicles waiting in line to enter a parking lot can be modeled by the function f left parenthesis x right x squared over 2 left parenthesis 1 minus x right parenthesis endfraction , where x is a number between 0 and 1 known as the traffic intensity. find the rate of change of the number of vehicles waiting with respect to the traffic intensity for the intensities (a) xequals0.3 and (b) xequals0.6.