If you have 9 divers total and each team can only have 4 divers, then logically the US can select 2 teams of 4 from 9 divers.
ANSWER
A) 9.4 * 10^-8, 9.25 * 10^-6, 2.5 * 10^3, 7* 10^3
EXPLANATION
The numbers are given in standard form.
The first criteria we will use to order them is the exponents.
The bigger the exponents the bigger the number.
The second criteria is that, if the exponents of any two numbers are the same, then we use the numbers multiplying the powers of 10 to order.

The correct choice is A.
Basically the answer is 6, if you'd like an explanation, let me know. :)
Answer: B = 9
Step-by-step explanation:
16-b=7
Rearrange so we can subtract 16 by 7
16 - 7 = 9
Substituting 9 for b and making sure it's correct.
16 - 9 = 7