I) Within the relevant range, which of the following is true regarding variable costs and fixed costs?

a. variable cocts per unit fluctuate and fixed costs per unit remain constant

b. variable costs per unit are constant and fixed costs per unit fluctuate

c. both total variable costs and total fixed costs are constant

b. both total variable costs and total fixed costs fluctuate.

II) Parts administration is an example of:

1. unit level activity

2. batch level activity

3. product level activity

4. organization sustaining

Appreciate the help.