Why does marginal cost decrease then increase.

What is the opportunity cost in this scenario? harry has been very busy at work for the past two weeks. he has been working weekends too. finally, he is going to get a weekend off. originally, he planned to paint his apartment that weekend. he also considered going fishing for the weekend. but then his parents called and asked him to come for dinner because it has been a while since they have seen each other. later on, his friend theo informed him about a surprise birthday party for another friend. theo plans to reserve a room at a restaurant for the celebration, with the cost to reserve the room split between theo, harry, and three other friends. now harry is confused about what he should do over the weekend. he decides that, for him, the most important commitments are going over to his parent's house and attending his friend's birthday party. in the end, harry decides to see his parents.

Alandowner entered into a written agreement with a real estate broker whereby the broker would receive a commission of 10% of the sale price if he procured a "ready, willing, and able buyer" for the landowner's property and if the sale actually proceeded through closing. the broker found a buyer who agreed in writing to buy the property from the landowner for $100,000, the landowner's asking price. the buyer put up $6,000 as a down payment. the agreement between the landowner and the buyer contained a liquidated damages clause providing that, if the buyer defaulted by failing to tender the balance due of $94,000 at the closing date, damages would be 10% of the purchase price. the landowner included that clause because she was counting on using the proceeds of the sale for a business venture that would likely net her at least $10,000. the buyer became seriously ill and defaulted. when he recovered, he demanded that the landowner return his $6,000, and the landowner refused. the broker also demanded the $6,000 from the landowner and was refused. the broker and the buyer filed separate suits against the landowner, with the buyer pleading impossibility of performance. the two cases are consolidated into a single case. how should the court rule as to the disposition of the $6,000?

Two assets have the following expected returns and standard deviations when the risk-free rate is 5%: asset a e(ra) = 18.5% σa = 20% asset b e(rb) = 15% σb = 27% an investor with a risk aversion of a = 3 would find that on a risk-return basis. a. only asset a is acceptable b. only asset b is acceptable c. neither asset a nor asset b is acceptable d. both asset a and asset b are acceptable