Contemual lvlet'wods The Riemann sums you evaluated in Problems 1 and 2 were approximations of net areas. For each function and context belovv. brieflv interpret the net area under the function's graph. Make sure you include units of any:I quantity Iyou mention. 1". If the function fix) =.5J gives the rate of change in revenue as the number of thousands of units 3: increases [i.e.. it is marginal revenue}, then the net area under y=fixji over [1,5] is