Consumption function and saving function

Using diagrams explain what a  consumption function is; clearly indicating and explaining autonomous consumption and the marginal propensity to consume (MPC). Explain what a  saving function is; clearly showing the relationship with the consumption function. Assume a closed economy.
” Foundations of Economics, David Begg (3rd edition, 2006, McGraw-Hill).
” Economics, Gregory Mankiw and Mark P. Taylor, Thomson Learning, 2006.
” Should include references in the Harvard Style
” Any Further economics books as a last option.