a$.$ The break$-$even quantity is

units if machine A is selected. $($Enter your response as a whole number.$)$

Part $3$

b$.$ The break$-$even quantity is

units if machine B is selected. $($Enter your response as a whole number.$)$

Part $4$

c$.$ If total demand for the product is believed to be $414,000$

units, which machine will make the greater contribution to profit?

The contribution to profit is $ if machine A is selected. $($Enter your response as a whole number.$)$