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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.

Abar magnet cut in half will form a total ofpoles. a)fourb)eightc)two

Scientific models are based on current knowledge, which can limit their effectiveness when new discoveries are made.