8. [0/1 Points] DETAILS PREVIOUS ANSWERS SCALCET9 15.4.032. MY NOTES ASK YOUR TEACHER PRACTICE ANOTHER (a) A Iamp has two bulbs, each of a type with average lifetime 1,700 hours. Assuming that we can model the probability of failure of a bulb by an exponential density function with mean [1 = 1,700, find the probability that both of the lamp's bulbs fail within 1,500 hours. (Round your answer to four decimal places.) x (b) Another lamp has just one bulb of the same type as in part (a). If one bulb burns out and is replaced by a bulb of the same type, nd the probability that the two bulbs fail within a total of 1,500 hours. (Round your answer to four decimal places.) _x