The table displays the velocity of sound in various materials.
Speed
Substance (meters per second)
Air
Water
Rock
344
1,437
3,000
Based on the data presented in the table, which of the following boys would be able to hear a rock falling off a cliff one kilometer away?
(1 point)
a boy swimming in the water
• a boy sitting on the grass
a boy lying down with his ear to the ground
a boy sitting in a tree with his ear to the bark