Which three of the following are characteristic of Friedman's 'Permanent Income Hypothesis'? a) The main influence on long-run consumption is 'transitory income' b) The main influence on long-run consumption is some form of long-run average income c) The long-run consumption function will tend to be steeper than the short-run consumption function d) The long-run consumption function will tend to be flatter than the short-run consumption function e) Consumption will tend to be a constant proportion of long-run average income (permanent income)