10. (10 points) An executive must decide between two competing techniques to complete a given task. Technique A will work only 15% of the time, but only costs $300. Technique B will work $5% of the time and costs $5000, The executive must balance time versus cost, so he decides on the following rule Try technique A for a set number of times, A. If it doesn't work, switch to technique B and keep trying that until success occurs. He must therefore find the expected number of attempts and the expected cost for various values of the variable A. a. Give a probability mass function for the number of attempts if A-3. b. Write, but do not evaluate, the formula for expected number of attempts with A-J. c. Give a probability mass function for the cost of success if 4-2. d. Write, but do not evaluate, the formula for the cost of success for A-2. c. (5 points extra credit) Evaluate the formulas you found in b and d