An airline company offers four fairs as shown in the table below. The demand distribution for each fare is normal with mean and standard deviation as given in the table. Find an estimate of the protection levels for the classes using the heuristic EMSR-b. Class Fare mean stdev

1. 1100 17.5 6.8

2. 1050 45.5 16

3. 650 39.5 14.2

4 350 33 11.3

Class Protection Level 1 2 3