Piaget's preoperational stage is so named because he believed that children in this stage of development: are unable to reason. cannot yet form stable concepts. cannot yet perform reversible mental actions. cannot operate electronic devices like tvs.

When something is moving, it is in motion. pressing the gas pedal in a car will put the car in motion. two important properties of motion are speed and direction. speed is how fast an object is moving. tony and tanya both run for the same amount of time, in the same direction. tanya runs much further than tony in that time. how does tony's speed compare to tanya's speed? a) their speed is equal. b) tony is slower than tanya. c) tony is faster than tanya. d) without a stopwatch, you can't say for certain.

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.

Advances in technology generally result a.) a higher standard of living for everyone b.) greater productivity c.) more jobs for everyone d.) more government regulation