Advertising agencies typically receive

a$)$ a $25\%$ commission paid by the media from which it makes purchases.

b$)$ a $15\%$ commission paid by the media from which it makes purchases.

c$)$ large fees from the companies whose als they develop and place.

d$)$ a $10\%$ commission from the advertising company and $10\%$ from the media the

e$)$ a $15\%$ commission from the company whose product they are helping advertis