If the government sets a rule for the public sector firm to accept the fixed price, then, the monopoly firm will have to behave like a perfectly competitive firm and will be a price taker. In this case, the price fixed (Pe), as set by the government, will equate the demand and the supply, which will determine the equilibrium point 'E'. At the price Pe, the firm earns normal profit, i.e. zero economic profit.
Equilibrium price = Pe (fixed by the government)
Equilibrium quantity = Qe
Profit = Normal profit.