$1.$ Consider a room which is $6$m x $5$m x $3$m high. The room has two standard glass windows $2$m x lm each and a solid wood door which is $2\mathrm{.}2$m x $1$m x $5$cm thick. The room has a mineral fiber tile ceiling, smooth plaster on lath walls, and a carpet over concrete floor. $($a$)$ Find the overall absorption coefficient. $($b$)$ The sound pressure level due to a noise source was measured and the results are given below. If a worker stays in this room for $8$ hours per day, are the OSHA rules violate? If the OSHA rules are violated, determine the absorption materials to be installed on the four wall surfaces and thus to meet the OSHA requirements. Frequency $63125250500100020004000$ Lp $($dB$)84100959089831275$Consider a room which is $6m5m3m$ high. The room has two standard glass windows $2mlm$ each and a solid wood door which is $2\mathrm{.}2m1m5cm$

thick. The room has a mineral fiber tile ceiling, smooth plaster on lath walls, and a carpet over concrete floor.

$($a$)$ Find the overall absorption coefficient.

$($b$)$ The sound pressure level due to a noise source was measured and the results are given below. If a worker stays in this room for $8$ hours per day, are the

OSHA rules violate? If the OSHA rules are violated, determine the absorption materials to be installed on the four wall surfaces and thus to meet the OSHA

requirements.