Costs associated with two alternatives, code-named Q and R, being considered by Lang Corporation are listed below:

	Alternative Q	Alternative R
Supplies costs	$ 63,500	$ 63,500
Power costs	$ 37,000	$ 20,100
Inspection costs	$ 11,800	$ 27,500
Assembly costs	$ 38,200	$ 29,100

Required:
a.	Which costs are relevant and which are not relevant in the choice between these two alternatives?

Supplies costs	(Click to select) Relevant Not relevant
Power costs	(Click to select) Relevant Not relevant
Inspection costs	(Click to select) Relevant Not relevant
Assembly costs	(Click to select) Not relevant Relevant

b.	What is the differential cost between the two alternatives? (Negative amount should be indicated by a minus sign. Omit the "$" sign in your response.)

Total differential cost

$