I will assume here that the well is sufficiently short so that the time the sound takes to come from the bottom of the well to our ear is negligible.
Since the pebble moves by uniformly accelerated motion, the distance it covers is given by

where

is the gravitational acceleration

is the time the pebble takes to reach the bottom of the well
Therefore, the depth of the well is

and the correct answer is B.
Answer:
•Helps to maintain va proper pH in the body which supports cell function.
•Carries electrolytes such as sodium and potassium to our muscles.
Through the compact molecules of a solid sound would move at its slowest.
Through the loose molecules of a liquid sound would move moderately.
Through the very spacious molecules of a gas sound would move very fast.
Given mass= 1kg
Weight on earth = mg(gravity of earth) = 9.8N
weight on moon = mg(gravity of moon)= 1.62N
weight on outer space mg(gravity outer space = 0) = 0N
Explanation:
You can simply subtract the atomic number from the mass number in order to find the number of neutrons. If the atom is neutral, the number of electrons will be equal to the number of protons.
Remember!
1. Your mass number is the total number of neutrons and protons within the atom.
2. Your atomic number is the amount of protons within the atom.
3. For neutral atoms, the electron number is the same as the atomic number.