Let P(t) give the total number of people getting a particular disease t days since the disease was first detected. The graph of P(t) and a table of values for P '(t) are shown below. P '(t) 120 178R 1662 2 24 1482 1194 4 84 840 6 114 564 420 R 8 222 120 10 12 14 10 84 12 42 14 120 Determine an exact value of (p-1) . (840) . Express your answer in the appropriate units. (P-1) ' (840) - Units of (P-1) ' (840) [---Select