Answer:
20 ms⁻¹
360 J
Explanation:
Kinetic energy is the energy possessed by a moving object solely due to its motion.
You can get the K.E. of an object using the equation,
K.E. = (1/2)mv² where all terms in usual meaning
So you get,
K.E. = 36000 = (1/2)×180×v²
v = 20 ms⁻¹
Also,
K.E. = (1/2)×80×3² = 360 J