What is the source of the supply of loanable funds?

Why do almost all models begin with assumptions?

What will be an ideal response?

Consumers derive consumer surplus whenever

a. the monetary value of total utility equals total expenditure b. the monetary value of total utility is greater than total expenditure c. the monetary value of total utility is less than total expenditure d. marginal utility is greater than total utility e. marginal utility is less than total utility