Please help with this.

In 1990, the average income for an american worker was $1,518 per month. in 2000, the average income for an american worker was $2,632 per month. during this time period, a basket of necessities (food, housing, etc.) increased from $657 per month in 1990 to $1,402 per month in 2000. the real value of income ▼ increased decreased over that 10-year period.

Which groups of people most directly benefited from song innovations in the song dynasty‘s open border policy?

Which statement is a good description of a model? a) models are a description of nature based only on one or two variables. b) models are testable ideas but they are not very to most people. c) models are a description of nature that predicts more accurately than real events. d) models are an approximiation of a real system that omits all but most essential variables in a system.