Answer: the first answer choice is the answer i think it is at least
Step-by-step explanation:
Answer:

Step-by-step explanation:
Your answer was mostly correct. Just change < into 
Ratio=4.0 *10⁷ Krill / day
amount of krill=ratio * days
amount of krill=(4.0*10⁷ Krill /day)(3.65*10² days)=1.46*10¹⁰ krill
Answer: 1.46*10¹⁰ krill
3) Mathematical expression would be:
412 - 65 + 0.50x
Where, x = Number of Texts sent
4) Product means result after multiplication, sum after addition, quotient is the result of division with remainder, and difference is how far two numbers are in their magnitude.
"Per" tells us the magnitude for an Unit value.
5) Associative property = (a+b) + c = a+ (b+c)
Commutative property = a + b = b + a
Distributive Property = a(b+c) = ab+bc
They all have their unique characteristics and can be differentiated on that basis.
6) They all are same.
At the end, without parentheses and in proper symbol, it would be equal to -3/4
Hope this helps!