The major sources of funds for the U.S. Federal government include the following, except:

In a graph, a line has a negative slope if

A) the line is vertical. B) the line is horizontal. C) the line rises from right to left. D) the line rises from left to right.

Consumers don't care which supplier they buy from in a perfectly competitive market because:

A) the outputs of the firms in a perfectly competitive market are all the same. B) the consumers have no choice regarding who they buy from. C) price is always low enough that the choice of supplier doesn't matter. D) all of the above.