Tangent Lines to Differential Equations v, Milt" 30'J 4:59:2'i F'M I II watch help video The quantity of a substance can be modeled by the function B (t) that satises the differential equation (if? = % (B 100) . One point on this function is B (U) = 250. Based on this model, use a linear approximation to the graph of B at t : U to estimate the quantity of the substance at t : U. 1