What would be the new pressure if a 400 mL gas sample at 380 mm Hg is expanded to 800 mL with no change in temperature

25 atm or 190mmHg

Explanation:

Since Temperature is constant we dont need to worry about it so.

P1V1=P2V2

Rewritten as (P1xV1)/V2 Always use liters in gas laws

I Prefer atm so ill convert to that to use in the equation.

(.5atmx.4L)/.8L =.25 atm or 190mmHg

(You can convert mmHg to atm by dividing by 760)

the answer is b because, investigating whether another species of moth also drinks tears might be interesting, but it would not directly explain why this species of moth does.

to explain why this species of moth drinks tears, the scientist could ask: "what nutrients that moths need are in elephant tears? "

the scientist could experiment with moth repellent or oter ways to keep the moths away, but that would not answer his original question.

nuclear fission produces elements that are heavier than helium.

the elements that are used in nuclear fission and their products are much heavier than helium.