Suppose that the life expectancy of a certain brand of nondefective light bulbs is normally distributed, with a The number of light bulbs that will last between 1240 hr and 1370 hr is mean life of 1300 hr and a standard deviation of 50 hr. If 60,000 of these bulbs are produced, how many will last between 1240 hr and 1370 hr? (Round to the nearest whole number.)A teacher gives a test to a large group of students. The results are closely approximated by a normai curve. The mean is 77, with a standard deviation of 7. The teacher wishes to give A's to the top 8% of the students and F's to the bottom 8%. A grade of B is given to the next 16%, with D's given similariy. All other students get C's. Find the bottom cutoff for a grade of C. The bottom cutoff for a C is . (Round to the nearestwhole number as needed.)