A cement manufacturer has supplied the following data: Cement produced and sold (220,000 Ton), sales revenue ($924,000), variable manufacturing expense ($297,000), fixed manufacturing expense ($280,000), variable selling and administrative expense ($$165,000), fixed selling and administrative expense ($82,000) and net operating income ($100,000). What is the company's unit contribution margin?

a. $0.45

b. $1.90

c. $2.10

d. $4.20

Within the relevant range, variable costs can be expected to:

a. increase on a per unit basis as the activity level increases

b. Differ (vary) in total in direct proportion to changes in the activity level

c. increase on a per unit basis as the activity level decreases

d. remain constant in total as the activity level changes

Please please, I don't have enough time to help me