A. Solid turns into a gas
Answer:
I don't know what do u. mean
<h2>
Answer:50
</h2>
Explanation:
Let
be the airspeed.
Let
be the cross wind speed.
We know that,ground speed is the vector sum of airspeed and cross wind speed and airspeed is perpendicular to cross wind speed.
If
and
are two perpendicular vectors,the resultant vector has the magnitude 
Given,

So,the ground speed is 
Wave speed = frequency * wavelength
Wave speed = 4 * 25
Wave speed = 100 m/s