Answer:
344.8 Hz
Explanation:
The frequency of a wave is given by:

where
v is the speed of the wave
is its wavelength
Here we have
v = 793 m/s

Substituting into the equation, we find

Acceleration = (change in speed) / (time for the change)
-- You said that the airplane has to speed up from zero ("sitting") to 40 m/s, so the change in speed is 40 m/s.
-- You said that it has to roll for 10 seconds to build up enough speed to take off, so the time for the change is 10 s .
Acceleration = (40 m/s) / (10 s)
Acceleration = (40/10) (m/s)/s
<em>Acceleration = 4 m/s²</em>
That seems like no problem. It's only like about 41% of 1 G . That would not even spill the drinks in First Class, or wake up the passengers who are already asleep (like me).
The correct answer of the given question above would be option C. In 1947 Thor Heyerdahl sailed a simple raft from Peru to Polynesia, following the ocean currents for more than 6,000 kilometers.<span> This statement accurately describes what Heyerdahl proved by this voyage. It would have been possible for people from ancient Peru to reach Polynesia by following ocean currents. </span>
<span>The forth I think, conserving water is useless if it is just going to be contaminated in unsanitary conditons
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