Break$-$even point

Diamond Jim's makes and sells class rings for local schools. Operating information is as follows:

a$.$ What is Diamond Jim's break$-$even point in rings?

$$ rings

b$.$ What is Diamond Jim's break$-$even point in sales dollars?

c$.$ What would Diamond Jim's break$-$even point be in rings if sales commissions increased to $$54$ per ring?

Note: Round your final answer up to the nearest whole unit $($for example, round $5\mathrm{.}1$ to $6$ units$).$

$x$ rings

d$.$ What would Diamond Jim's break$-$even point be in rings if fixed selling expenses decreased by $$6,000?$

Note: Round your final answer up to the nearest whole unit $($for example, round $5\mathrm{.}1$ to $6$ units$).$

$x$ rings