Please help.. I would like the explanation as well as the answer .

How do businesses a country's economy? a. by investing in goods and services b. by increasing the unemployment rate c. by making profits

Add the fractions, and simply the result to lowest terms. 2/3 + 2/7= ?

Dean and karlene get paid to write songs. dean is paid a one-time fee of $20 plus $80 per day. karlene is paid a one-time fee of $25 plus $100 per day. write an expression to represent how much a producer will pay to hire both to work the same number of days on a song.