The fixed cost of a toy manufacturing company is $$1$ million annually. The main product has revenue of $$8\mathrm{.}50$ per unit and $$4\mathrm{.}25$ variable cost. Determine the following.

$($a$)$ Breakeven quantity per year.

$($b$)$ Annual profit if $200,000$ units are sold and if $350,000$ units are sold.