Answer:
B: Inserting a gene from a flounder into salmon DNA to produce antifreeze proteins.
Explanation:
Hope this helps.
Answer:
Because of oxygen toxicity.
Explanation:
Oxygen toxicity.
Oxygen has been known to cause central nervous system (CNS) toxicity when the pressure gets higher. This toxicity can cause convulsions, and this can cause the diver to drown.
The current standard maximum safe oxygen working pressure is 1.4 atm ppO2. This is equal to 56.5m/185′ when breathing air (21% O2 / 79% N). Below that depth the fraction of oxygen in a breathing gas must be reduced, and in order to maintain this maximum pressure of 1.4 ppO2, Helium must be added.
I believe it's 6789 times 10^4. I could be wrong, due to the fact that I don't remember what's the definition of the scientific notion. I hope this helps, or at least gives you an idea! :D