A lightbulb manufacturer has found that the amount of time their lightbulbs work is normally distributed with a mean of 500 hours and a standard deviation
of 50 hours. In a random sample of 1,500 of lightbulbs, which of the following is
closest to the expected number of lightbulbs that would work for more than
600 hours?
240
38
1,462
2

You work for a landscape company that just got a contract to re-mulch a park. the area that needs mulching is 30 feet by 60 feet. they want a 3 inch layer of much on the area. the company has bags of mulch that cover 2 cubic yards that cost $4.00 per bag. how much will it cost the consumer just in materials to re-mulch the area (round to the nearest dollar)?