A building with a 3,200 saft. flat roof has a single downspout with a height of 5 m and cross-section of 4 in2. In an interval of 24hrs about 2.0 inches of rainwater is accumulated on the roof as the drain is clogged. How long will it take for the water to drain after the downspout is unclogged? Consider that as water drains the change in height of water accumulated on the roof is negligible. Select one: O a. 323 s O b. 380 s O c. 591 s O d. 639 s ? Clear my choice