(bounds of the firm) ashland oil, inc., buys its crude oil in the market. larger oil refiners, such as texaco, drill for their own crude oil. why do some oil companies drill for their own crude oil and others buy crude oil in the market?

U.s. internet advertising revenue grew at the rate of r(t) = 0.82t + 1.14 (0 ≤ t ≤ 4) billion dollars/year between 2002 (t = 0) and 2006 (t = 4). the advertising revenue in 2002 was $5.9 billion.† (a) find an expression f(t) giving the advertising revenue in year t.

(a) what was the opportunity cost of non-gm food for many buyers before 2008? (b) why did they prefer the alternative? (c) what was the opportunity cost in 2008? (d) why did it change?

Who is not spending wisely? erika goes shopping and saves her receipts. she totals how much she spent and writes it down. mia needs to buy a new pair of shoes because she joined the soccer team. she looks at newspaper ads to find the best price. lauren has been thinking about getting a puppy for a long time. she walks by the pet store at the mall and decides to get a puppy. erin makes a purchase online using a credit card. she knows that she can pay the entire bill when it arrives.