A hotel numbers its fare classes from higher to lower as $1,2,3,$ and $4.$ The room prices for these classes are

$$400,$

$$300,$

$$200,$ and

$$100.$ The demands for these fare classes are denoted by D$1,$ D$2,$ D$3,$ and D$4.$ These demands turn out to have normal distributions with the following means and variances:

D$1$ in N$(5,2),$ D$2$ in N$(5,2),$ D$3$ in N$(5,2),$ D$4$ in N$(5,2).$

a$)$ Use EMSR$-$a heuristic to find the protection level

for classes $\{1,2,3\}?$

$[$ Select $]$

b$)$ Use EMSR$-$a heuristic to find the protection level

for classes $\{1,2\}?$

$[$ Select $]$

c$)$ Use EMSR$-$a heuristic to find the protection level

for class $\{1\}?$

$[$ Select $]$