Question \( 4 \) A company produces a certain item. The costs of production at two levels of output are:
At a production level of \( 32,000 \) items the cost is \( 485,000 \)
At a production level of \( 43,000 \) items the cost is \( 639,000 \)
Calculate the cost of producing \( 40,000 \) items.
Question \( 5 \)
Three taps, A, B and C are emptying a tank. Tap A can empty the full tank in \( 6 \) hours, tab B in \( 8 \) hours. If all taps are open together, it would take \( 2.66667 \) hours to empty the tank. How long (in hours) would it take tap C by itself to empty the tank? Marks