c. The width of a line etched on an integrated circuit chip is normally distributed with mean 3.000 m and standard deviation .140. What width value separates the widest 10% of all such lines from the other 90%?

40. The article “Monte Carlo Simulation—Tool for Better Understanding of LRFD” (J. Structural Engr., 1993:

1586–1599) suggests that yield strength (ksi) for A36 grade steel is normally distributed with
43 and
4.5.

a. What is the probability that yield strength is at most 40?

Greater than 60?

b. What yield strength value separates the strongest 75%

from the others?