Refraction is the bending of light (it also happens with sound, water and other waves) as it passes from one transparent substance into another. This bending by refraction makes it possible for us to have lenses, magnifying glasses, prisms and rainbows. Even our eyes depend upon this bending of light. Hope this helps!
Answer:
So trees in temperate don't lose their leaves because the weather events aren't harsh enough.
Trees in tropical rainforest don't lose their leaves because they are a different type of tree known as evergreens that are green all year round.
Explanation:
Ok so first we'll define some things
Deciduous Trees= Trees that lose all of their leaves for part of the year.
Trees shed their leaves trees to try and survive harsh weather events.
Temperate deciduous trees lose their leaves in fall to better survive the winter conditions of extreme cold and reduced daylight.
Temperate rainforests = An area that doesn't experience extremely cold or extremely hot temperatures or what we would call harsh weather events.
Broad-leaved trees in tropical rainforests are known evergreen, they are known as this as they are green all year round.
False that atom is the smallest identifiable unit of a compound.
The smallest identifiable unit of a compound is the Element. Element is the one which make up the compound and element is made up by atoms. Example of element is oxygen and hydrogen which make up water (H2O) which is a compound.
Answer : The correct option is, (B) 
Solution :
According to the Graham's law, the rate of effusion of gas is inversely proportional to the square root of the molar mass of gas.

or,
..........(1)
where,
= rate of effusion of unknown gas = 
= rate of effusion of oxygen gas = 
= molar mass of unknown gas = ?
= molar mass of oxygen gas = 32 g/mole
Now put all the given values in the above formula 1, we get:


The unknown gas could be carbon dioxide
that has approximately 44 g/mole of molar mass.
Thus, the unknown gas could be carbon dioxide 
The rate<span> of a </span>reaction increases<span> if the temperature is increased, the concentration of a dissolved reactant is increased and the pressure of a </span>reacting<span> gas is increased. Hope this answers the question. Have a nice day. Feel free to ask more questions.</span>