Question 672687
I suggest you purchase a TI-84+ calculator.
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(A) P(z > 0.90) = normalcdf(0.90,100) = 0.1841
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normalcdf sums up the area under the normal curve 
over the z-interval [0.9,100]
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(B) P(-1.17 < z < 0) = normalcdf(-1.17,0) = 0.3790
normalcdf sums up the area under the normal curve
over the z-interval (-1.17,0)
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(C) P(-0.58 < z < 1.57) = normalcdf(-0.58,1.57) = 0.4649 
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Cheers,
Stan H.
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