Answer - Ozone layer helps keep the harmful ultra violet rays hitting and keeping the atmospheric pressure in.
Reasoning - Without the ozone layer the whole planet would have a loss of water and especially people burning very easily from the sun. <span />
Helium is a chemical ELEMENT of the family of noble gases. Its chemical symbol is 'He' which has an atomic number of 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table. Although it doesn't really react under normal conditions, it is the second most abundant element in the universe.
Elements are pure substances that cannot be broken down any further.
The best description of the Bohr model of the atom is that the <span>atom consists of a nucleus with electrons orbiting at specific energy levels. Absorbed photons cause electrons to jump between energy levels. The answer is letter C.</span>
1. Iron fillings are magnetic, so use a magnet to pull the iron fillings out of the mix.
2. Then you can put the salt and sand mixture into water, since salt is soluble, and the salt will dissolve, leaving you with sand.
