Find the area under the standard normal curve to the left of a. z = 0.74 b. z = −2.16 c. z = 1.02 d. z = −0.15

A. z = 0.74
  The z-score of 0.74 translates to a percentile of 0.77035. Hence, the area under the standard normal curve to the left of z-score 0.74 is ~0.77.

b. z = -2.16
   This z-score translates to a percentile of 0.015386 which is also the numerical value of the area under the curve to the left of the z-score

c. z = 1.02
   The percentile equivalent of the z-score above is 0.846. The area is also 0.846.

d. z = -0.15
   The percentile equivalent and the area is equal to 0.44. 

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