Answer:
f=171.43Hz
Explanation:
Wave frequency is the number of waves that pass a fixed point in a given amount of time.
The frequency formula is: f=v÷λ, where <em>v</em> is the velocity and <em>λ</em> is the wavelength.
Then replacing with the data of the problem,
f=
f=171.43
f=171.43 Hz (because 
, 1 hertz equals 1 wave passing a fixed point in 1 second).
Joseph's experiment could be improved by using the same antenna at each part of the house during each trial instead of using different antenna. By doing so, he can obtain accurate results how is the signal in different part of the house under the same conditions (despite the location). So, he will see the dependence of the signal on the location. If he uses different antenna, than this antenna can also have influence of the signal.
Answer:
F(Mars) = 2 G m M / (4 R)^2 force of Sun on Mars
F(Merc) = G m M / R^2 force of force of Sun on Mercury
R = distance of Sun from Mercury, m = mass of Mercury
F(Merc) / F(Mars) = 4^2 / 2 = 8
