What is kinetic energy of a particle of mass 2 kg moving with a speed of 20 m/s?

(A) 340 joule
(B) 360 joule
(C) 380 joule
(D) 400 joule

The answer is: (D) 400 joule
KE=(1/2)mv² = (1/2)2(20)² = 400 joule