Why is it important to look at external sources of information when exploring product and service information?

Jaynet spends $30,000 per year on painting supplies and storage space. she recently received two job offers from a famous marketing firm – one offer was for $85,000 per year, and the other was for $120,000. however, she turned both jobs down to continue a painting career. if jaynet sells 40 paintings per year at a price of $4,000 each:

Goods and services that can be used for the same purpose are and goods and services that are used together are

Which term refers to the cost that motivates an economic decision