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The frequency F of a fire truck siren heard by a stationary observer is given below, where ± v represents the velocity of the accelerating fire truck in meters per second (see figure). (Round your answers to 3 decimal places).
F = 131,500/321 ± v
1.a) Find the rate of change of F with respect to v when the fire truck is approaching at a velocity of 28 meters per second (use −v).
F '(−28) =
(B) Find the rate of change of F with respect to v when the fire truck is moving away at a velocity of 28 meters per second (use +v).
F '(28) =

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The frequency F of a fire truck siren heard by a stationary observer is given below, where ± v represents the velocity of the accelerating fire truck in meters per second (see figure). (Round your answers to 3 decimal places).
F =  	131,500/321 ± v
1.a) Find the rate of change of F with respect to v when the fire truck is approaching at a velocity of 28 meters per second (use −v).
F '(−28) =
(B) Find the rate of change of F with respect to v when the fire truck is moving away at a velocity of 28 meters per second (use +v).
F '(28) =