Force A has a magnitude F and acts for the time Δt, force B has a magnitude 2F and acts for the time Δt/3, force C has a magnitude 5F and acts for the time Δt/10, and force D has a magnitude 10F and acts for the time Δt/100. Rank these forces in order of decreasing impulse.

Your target variable is δf, the magnitude of the difference in frequency between the waves emitted from the sonar device and the waves received by the device after reflecting off the whale. write an expression for δf in terms of the relevant frequencies using the subscript notation introduced above.