A sector with a central angle measure of \purpleD{\dfrac{7\pi}{4}} 4
7π
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start color #7854ab, start fraction, 7, pi, divided by, 4, end fraction, end color #7854ab (in radians) has a radius of \maroonD{16\,\text{cm}}16cmstart color #ca337c, 16, start text, c, m, end text, end color #ca337c.

1. according to the internal revenue service, the mean tax refund for the year 2007 was $2,708. assume the standard deviation is $650 and that the amounts refunded follow a normal probability distribution. a. what percent of the refunds are more than $3,000? b. what percent of the refunds are more than $3,000 but less than $4,000? c. what percent of the refunds are less than $2,000?