Because the airplane flies at 800 km/h, it will fly 800 km in 1 hour. In order to find how far it travels in 2 hours, we multiply this number by 2. 800*2 = 1600, so the plane will travel 1600 km in 2 hours.
Imma guess A! Idk if it’s 100% correct tho so I’d check that!
The acceleration and distance is related to the following expression:
y=v0*t + a*t^2/2 ; v0=0
y=44.1*100/2 = 2205m
hence, the speed will be
v=0 + a*t = 441m/s
from that height it will just be subjected to the gravitational acceleration
0=v_acc^2 -2g*y_free
y_free = v_acc^2/2g = 9922.5m
<span>y_max = y_acc+y_free = 441+9922.5 =10363.5m</span>
The observer can conclude that the sound is moving away from them and that its speed is increasing.