8. [8 marks] The graph of the first derivative f' of a function f, having a domain from [0, co), is shown to the right. VA (a) On which intervals is f increasing and on which intervals is f decreasing? y = f'(x) 0 2 4 6 8 X (b) At which values of a does f have a relative maximum and at which values of x does f have a relative minimum? (c) On which intervals is f concave upward and on which intervals is f concave downward? (d) What are the r-coordinates of the inflection points of f