The kinetic energy of any moving object is
K.E. = (1/2) (mass) (speed)² .
To use this simple formula, the 'mass' has to be in kilograms,
and the 'speed' has to be in meters-per-second.
You can see that we have a slight problem that has to be cleaned up:
The speed in the question is given in "kilometers per hour", but we'll
need it in "meters per second". So let's convert that right now:
(600 km/hour) x (1 hour / 3600 seconds) x (1000 meters / km)
= (600 x 1 x 1000 / 3600) (km-hour-meters / hour-second-km)
= 166.67 meters/second .
Now we're ready to plug numbers into the formula for K.E.
(1/2) (mass) (speed)²
= (1/2) (80,000 kg) (166.67 m/s)²
= (40,000 kg) (27,777.8 m²/s²)
= 1,111,111,111 kg-m²/s²
= 1.1... x 10⁹ Joules (choice D)