$($C$)$ In the same building, there is an open teaming area $(20$ ft by $30$ ft with a $9\mathrm{.}5$ ft ceiling$)$ for the accounting department, and you$$ve decided to use the same luminaires and selected a target initial illuminance of $40$ fc$.$ The coefficient of utilization for the luminaire in these room conditions is $0\mathrm{.}85.$ How many luminaires will be needed for this space? Round to the nearest whole number. $(5$ pts$)$