Imagine a firm's marginal abatement cost function with existing technologies is: MAC = 8 - E. If the firm adopts new pollution abatement technologies, its marginal abatement cost function will be: MAC = 4 - 0.5E.If the government raises the tax on emissions from $1 to $3, the benefits of adopting the new technologies increase by $____.

Select one:

a.$8.

b.$10.

c.$2.

d.$4.