Tiffany gives $50 to Jeremy for his birthday. This is an example of a(n)

In the above figure, what is the amount of the tax per compact disc?

A) $10 B) $20 C) $30 D) $40

If the price of a resource increases, other things constant, less of that resource will be hired because

a. producers will substitute away from that resource b. producers fear starting a trend toward higher resource prices c. the demand curve for the product will shift to the left d. highly paid resources don't produce as much e. it makes other resources look expensive as well