A supplier and a retailer have a long, well$-$established relationship with one another. All earlier contracts between them have contained a term that required payment be made within $30$ days of delivery. In the most recent contract between them, there was no term about payment at all. Which of the following would a court most likely use in deciding whether payment was due within $30$ days in the most recent contract?

$($a$)$ Ordinary trade customs

$($b$)$ Prior dealings between the parties

$($c$)$ Business efficacy

$($d$)$ Statutory requirements

Fred makes an offer to buy a house, but he wants to perform a building inspection first. If the building inspection is not good, then Fred does not want to purchase the house. Bill, the seller, agrees to this. What is the name of the clause that allows Fred to cancel the contract if the building inspection is not good?

$($a$)$ A liquidated damages clause

$($b$)$ A limitation of liability clause

$($c$)$ A condition precedent

$($d$)$ A condition subsequent

Holding a gun to someone's head and making them sign a contract is an example of:

$($a$)$ Unconscionability

$($b$)$ Misrepresentation

$($c$)$ Duress

$($d$)$ Undue influence

Mary, an elderly widow, entered into a contract to have new siding installed on her house. She has discovered that the fee that she agreed to pay is more than double what is usually charged for similar work. What does Mary have to prove in to support an argument that the contract she signed is unconscionable?

$($a$)$ She must prove that the salesperson threatened her with harm

$($b$)$ She must prove that she and the salesperson had a prior relationship with one another that was based on trust

$($c$)$ She must prove that she didn't have the mental capacity to understand the contract

$($d$)$ She must prove that there was an inequality of bargaining power between her and the salesperson and that it is a very bad bargain for her