Which of these is true about the big bang model? A. The singularity is an established, well defined part of the model.
B. Cosmic expansion stopped at some point in time.
C. Part of its proof is the amounts of H and He we have in the universe today.
D. The Big Bang was a Big explosion that threw matter into many different directions.

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.