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All can be found using normal distribution table:

a) z = 1.17

b) z = 1.75

c) z = -2.41

d) We have P(0 > Z > z) = 0.1429

By linear interpolation, z = -0.3662

e) So to speak, we have to find z such that:

P(Z < z) = 0.2586 + P(Z < -2.1) = 0.2765

Hence P(Z > z) = 0.7235

Using linear interpolation, we have z = -0.5933

By linear interpolation