The speed of light in a medium is measured to be 138,274,140 m/s, what is the refraction index for the medium?

Keneila is attempting to ski down a 20 m high friction free hill for the first time. she has a speed 10 m/s at the top. what is her kinetic energy when she is a the bottom, 20 m ? (a)2500 j (b)9800 j (c)12300 j (d)3100j (e)15000j

With i really need the correct answer!

What quantity do units represent in value