A city is planning to install an elevated storage tank for drinking water supply. The equalization volume is determines to be $40\%$ of the maximum daily demand. The average daily is estimated at $1\mathrm{.}5$ MGD$,$ and the peak factor recommended is $2\mathrm{.}0.$ The high and low water levels in the storage tank must be designed so that the variation in the water pressure leaving the tank does not exceed $10$ psi. the minimum diameter of the tank is most nearly $/$ a$)67$ ft$,$ b$)95$ ft$,$ c$)110$ ft$,$ d$)140$ ft