Answer:
For H2O, there is one atom of oxygen and two atoms of hydrogen. A molecule can be made of only one type of atom. In its stable molecular form, oxygen exists as two atoms and is written O2. to distinguish it from an atom of oxygen O, or ozone, a molecule of three oxygen atoms, O3.
Explanation:
The atoms furthest from the nucleus
First we have to calculate the time taken to travel the distance 30 m, is
.
Now from equation of motion,

Given,
.
As object starts from rest, so u = 0.
Substituting these values in above equation, we get
.
Thus, the acceleration is 
<span>If you have only two
data from two recording stations then you will be having a hard time finding
the correct location of the epicenter. This is because triangulation method requires
3 recording station. If you have 2 recording station, the 2 circles will
intersect at 2 points giving you 2 locations that could possibly be the
epicenter.</span>
C Camera. I think this because you can make timelapses with cameras which makes it easy to see.