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Monomous consumption is a, the change in consumption that results as a person's (or nation's) income increases or decreases. O b. that portion of total consumption that is dependent upon the level of income. O c the steady increase in the consumption of goods and services that automatically occurs as a person grows from a child to an adult O d. that portion of total consumption that is independent of the level of income. QUESTION 21 Suppose that the marginal propensity to consume is 0.8, and investment spending increases by $100 billion. The increase in aggregate demand (Le. expenditure) is: O a. $100 billion, the same amount as investment spending. O b. $125 billion, composed of $100 billion in investment spending and $25 billion in consumption. O c. $80 billion, composed of $100 billion in investment spending and a decrease in consumption of $20 billion, O d. $500 billion, composed of $100 billion in investment spending and $400 billion in consumption. QUESTION 22 According to Keynesian economics the most important factor affecting a household's consumer spending is O a, its expected future disposable income. O b. its current disposable income. O c. His wealth O d. the current interest rate