A roller coaster containing 3 cars is accelerating at 10 m/s before it comes to an abrupt stop at the end of the ride. The mass of one car is 300kg. How much force was exerted on the roller coaster to bring it to a stop?

Which of the following is a problem in the health care system of the united states? a. too many doctors in rural areas b. too many doctors who are general practitioners c. fraud d. costs that are too low

Characteristics of substistence farming include all of the following except a. the use of pesticidesb. shifting cultivation c. farmers that stay in one placed. the lack of tractors and machinery

Mankiw attributes – chapter 1 and his 10 principles – differences in living standards within a countryover time and across countries at a moment in time to: a. the presence or absence of inflation and unemployment. b. the allocation of resources between private markets and the public sector. c. those that have dealt successfully with the efficiency v. equality tradeoff and those that haven’t. d. differences in productivity. e. ones that think at the margin and respond to incentives and those that don’t.