A coal-burning steam power plant produces a net power of 300 MW with an overall thermal efficiency

Question:

A coal-burning steam power plant produces a net power of 300 MW with an overall thermal efficiency of 32 percent. The actual gravimetric air–fuel ratio in the furnace is calculated to be 12 kg air/kg fuel. The heating value of the coal is 28,000 kJ/kg. Determine
(a) The amount of coal consumed during a 24-hour period and
(b) The rate of air flowing through the furnace.