Because it is BELOW sea level after 10 minutes, it straight away cannot be A) or B), because ascended means going up, so it has to be either C) or D).
I believe the answer is C), as the answer for D) would be -40 meters per minute, but it's still 40. I'm not sure though, so it's either C) or D).
Answer:
Present Time
Let X= Eric's age (4/5)X= Seth's age
Question: What are their ages now?________________________________________________________________________
Past (21 years ago)
X-21 =Eric's age (4/5)X-21=Seth's age
2*[4/5(X-21]=Eric's age
Therefore, X-21= 2*[4/5(X)-21]=Eric's age Substitution
_______________________________________________________________________
X-21= 8/5 X - 42 Solve for "X" by adding 42 to both sides.
X-21+42=(8/5) X
X+21 = (8/5)X Subtract "X" from both sides.
21=(3/5)X Multiply both sides of equation by reciprocal of (3/5), which is 5/3
21*(5/3)= X Finish the problem to find value of "X," which is Eric's age.
Then find 4/5 (X)= Seth's age
Answer:
8,146 x 121
Step-by-step explanation:
This is a problem in which you need to measure your understading of "orders of magnitude."
If the estimated answer is
that means that we are looking at a multiplication in the "order of" 
You need to look at the "orders of magnitude" of the things you're multiplying. In the first case, we have
that would be "of the order of"
times
. So the whole multiplication would "of the order of"
or near 
The correct answer, 8,146 x 121, is because it's "of the order of"
times
and the gives us the
we need.
Volume = (Area of the base)x(Height)
66.85 = 15(H)
66.85/15 = H
H = 4.4567
The height is 4.4567mm.