Which of the following statements is false?

a. Sarah Salesclerk sells word processors on commission at Marlin's Department Store. She likes to sell the deluxe model because she earns a larger commission on it. One day, Carl Customer comes to the store to buy a word processor. Sarah tells him "This deluxe model will give you twice the wear and usage of the standard model." Based on that statement, Carl buys the deluxe model, which only lasts him six months. Sarah has committed fraud in the inducement.

b. At common law a promise under a seal to authenticate it was effective without anything more.

c. If no time is stated, an offer will terminate automatically after a reasonable period of time.

d. Death or insanity of either the offerer or the offeree terminates the offer.

e. Michael Merchant telephones an order for widgets to the manufacturer. Nothing is said by either party about the price or method of payment, but the manufaturer delivers the goods as requested. Michael has made an implied in fact promise to pay for the goods.