Pebbles of mass 0.1 kg are launched from the edge of a vertical cliff of height 5 m at a speed of 2 m/s. How fast will these pebbles be moving when they reach the ground if launched horizontally away from the cliff?
a. 10 m/s
b. 11.2 m/s
c. 9.9 m/s
d. 10.09 m/s