4. (From S&W 2.10-2.12) Compute the following probabilities: a. If Y is distributed N(1,4), find Pr(Y3) .8413 b. If Y is distributed N(50,25), find Pr(40Y52) .6326 c. If Y is distributed 210, find Pr(Y>18.31) .05 d. If Y is distributed F10,, find Pr(Y>1.83). .05 e. Why are the answers to (c) and (d) the same?