Answer: The reactants’ bonds break, and bonds of the products form.
Explanation:
When a chemical reaction takes place, the bonds are broken and new bonds are formed to make new molecules. Like when 2 water molecules are broken down to form hydrogen and oxygen.
solution:
You need to find the frequency, and they have already given you the wavelength. And since you already know the speed of light, you can use formula (2) to answer this problem. Remember to convert the nano meters to meters because the speed of light is in meters. 

Answer:
continental polar air masses
Explanation:
forms over Canada, move down from North Pole, bring bitterly cold and dry air to the northern United States during the winter.
Nuclear decay is the decay of atoms on the atomic scale. “Radioactive decay is the process by which an unstable atomic nucleus loses energy by radiation. A material containing unstable nuclei is considered radioactive. Three of the most common types of decay are alpha decay, beta decay, and gamma decay, all of which involve emitting one or more particles or photons.”