The answer is 13 feet. Please show me each step and explain how to get the answer.

Question:

Micah wants to make a rectangular concrete pad for his patio. The patio needs to be 6 feet long and 6

inches high. The price of the concrete is $56 per cubic yard. He needs $80.29. What is the width in feet

of the patio rounded to the nearest whole number? (12 inches=1 foot, 3 feet=1 yard)

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The answer to c. is 2 SD and the answer to d. is 3 SD

Please show each step and explain how you got the answers.

Question:

The average score on a math mid-term is 80 and a standard deviation of 0.8 is normally distributed.

c. By how many standard deviations would a score of 79 differ from the mean?

d. By how many standard deviations would a score of 82 differ from the mean?

Thanks