Compute the present value of $46,000, invested for six years at 8%. Present value of $1: 5% 6% 7% 8% 9% 3 0.864 0.840 0.816 0.794 0.772 4 0.823 0.792 0.763 0.735 0.708 5 0.784 0.747 0.713 0.681 0.650 6 0.746 0.705 0.666 0.630 0.596 7 0.711 0.665 0.623 0.583 0.547

When a company produces and sells x thousand units per week, its total weekly profit is p thousand dollars, where upper p equals startfraction 800 x over 100 plus x squared endfraction . the production level at t weeks from the present is x equals 4 plus 2 t. find the marginal profit, startfraction dp over dx endfraction and the time rate of change of profit, startfraction dp over dt endfraction . how fast (with respect of time) are profits changing when tequals8?