Which word is abstract?

garden
friendship
airplane
sunshine

The health care system in is referred to as a singleminus−payer health care system, and is a system in which the government provides national health insurance to all residents.

The graph represents price and output quantities under a monopoly what price will the monopolist firm set

Ascientist successfully predicts the outcome of an experiment. you watch carefully and know he didn't cheat. the scientist's success shows that: a) the scientist knows absolute truth about this experiment; success is not possible unless you know the truthb) the scientist was just lucky; no one ever knows what's going on, so successful predictions require luckc) the scientist may know the truth, or at least know something that is close to the truth, or the scientist may have gotten lucky this time; you can't be absolutely sured) the scientist really was cheating, even though you didn't see the cheating; no one can get things right, except by cheatinge) the scientist spent the night at a particular hotel chain and go a free breakfast, giving the scientist the ability to do amazing things