Hey there!
I believe the answer you're looking for is radio wave
Hope this helps!
Answer:
Killer T cells release enzymes that help destroy invading foreign matter (antigens), Helper T cells, on the other hand, stimulate another type of lymphocyte known as B cells. B cells produce antibody, which is a protein made in response to a specific antigen.
Answer: C) They can contain contaminants that can enter the air during storms or high winds.
Explanation: A is wrong because I got it wrong (Sorry, can't give much explanation there).
B is wrong because water contamination does not directly relate to respiratory health.
D is wrong because fertilizers can impact respiratory health (Explanation seems lack-luster, but I feel like this is common sense).
Hope this helps :)
Through a series of tests and data
Answer: D) By decreasing the activation energy of a reaction
A catalyst is a substance that speed up the rate of chemical reaction without affecting the product of the reaction. They only affect the rate of reaction not the yield of reaction.
Catalyst provide an alternative reaction pathway that has lower activation energy than that of uncatalysed reaction. It increases the frequency of collision and because of these greater collision which lowers the activation energy of the reaction.
