Brian purchased a rectangular-shaped granite countertop for the island in his kitchen. The granite slab measures 72 inches by 42 inches by 1.25 inches. If the density of granite is 170 pounds per cubic foot, how much does the
countertop weigh in pounds?

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How many $20 bills do you need to have to make $280

Assume that there is a 11% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on four independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?

Ana earns 2.5% simple interest on $2,000 in her savings account. she does not make any deposits or withdrawals. after 3 years, how much interest will ana have earned on her savings account?