The speed resulting from the plane is (3) 226 m/s
Reasoning:
We can determine the plane's resultant speed using the Pythagorean Theorem because the two speeds form a right angle (creating a right triangle).
Thus, the computation is as follows:


Consequently, the plane's resultant speed is (3) 226 m/s
Have a wonderful day!
The formula for the kinetic energy of any object in motion is
(1/2) (mass) (velocity²).
For the object you've mentioned, it translates to
(1/2) (100 kg) (12.5 m/s)²
= (50 kg) (156.25 m²/s²)
= 7,812.5 joules
______________________________
Beware that your attachment is heavily blurred and unreadable.