Most earthquakes occur along the edge of the oceanic and continental plates. The earth's crust (the outer layer of the planet) is made up of several pieces, called plates. The plates under the oceans are called oceanic plates and the rest are continental plates. The plates are moved around by the motion of a deeper part of the earth (the mantle) that lies underneath the crust. These plates are always bumping into each other, pulling away from each other, or past each other. The plates usually move at about the same speed that your fingernails grow. Earthquakes usually occur where two plates are running into each other or sliding past each other.
Answer:
A. All the molecules or atoms in motion have kinetic energy.
B. All the molecules or atoms in motion have thermal energy.
C. Each molecule or atom in motion has thermal energy.
D. Each molecule or atom in motion has kinetic energy.
Explanation:
The formula for specific gravity is:
where 
is the density of the substance and 
is the density of water.
The density of water, = 
Substituting the values in above formula we get,
The formula of density is:
The density of mercury is 
The mass of mercury is 
Substituting the values in density formula:
Answer:
First and seventeenth group.
Explanation:
Hydrogen is a special case as it has only one electron in its outermost orbital.
The hydrogen can lose or can accept electron easily.
Thus it can form positive ion similar to alkali metals and negative ion similar to halogens.
Thus it can fall into two groups
a) I group [Alkali metals]
b) 17th Group [Halogens]
