Junaidi has been working with Aloha Enterprise, which has two factory buildings:

East and West. He spends $50\%$ of his $8-$hours working time at each factory building. The noise level in each factory was measured, resulting in the following readings, as tabulated in Table $2,$ for various types of machines.

Table $2$: Noise monitoring at West and East Factory

$($a$)$ Calculate the cumulative noise exposure for Hamid, to decide whether the permissible exposure limit has been exceeded or not.

$($b$)$ Discuss any one type of administration control measure that can used to reduce the noise level to permissible exposure limit$.$