How tall are the wind turbines?

here's your answer..

Explanation:

For Doppler effect in radar the formula is as follows

Δf = f₀ x 2v /c

Δf is change in frequency in reflected wave , f₀ is original frequency , v is velocity of source and c is velocity of right .

Δf  = 2460 Hz , f₀ = 1.0525 x 10¹⁰ Hz , v = ? c is velocity of light .

2460 =  1.0525 x 10¹⁰ x 2 v / 3 x 10⁸

2460 = 105.25 x 2 v / 3

v = 2460 x 3 / (105.25 x 2 )

v = 35 .06 m /s .

(b)

Since the observed frequency is less , the source is moving away from the observer .

option (2) is correct .