Alright,
you will need to solve for each variable to find if they got the equation correctly or not..
Let's start with h
isolate h
(1/2)h = A/(b1+b2)
Now we need to get rid of 1/2 we may do so by multiplying both sides by 2
h = 2(A/(b1+b2))
And that's not how they did it for h so Option D doesn't apply
Let's see C
Also doesn't apply since they multiplied 2 only by A rather than A/h
Let's see B
Also not correct they made the same mistake as with option C
Let's see A
again same mistake
when multiplying both sides by 2
the 2 should be as following

I believe you should contact your instructor and explain that non of the options is right.
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6+4:2*10
6+2*10
<h2>26</h2>
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Answer:
The answer is D.
Step-by-step explanation:
It is given that Gabriella swims 2 laps for 1 minute. So in order to find how many minutes did he swim for each lap, you have to divide it by 2 :
2 laps = 1 minute
2 laps ÷ 2 = 1 minute ÷ 2
1 lap = 1/2 minute
= 30 seconds
Test :
Gabriella swim 1/2 min per lap. So if he swim 2 laps, you have to multiply it by 2 :
1/2 × 2 = 1 minute
Answer:
answer 1 b
Step-by-step explanation:
answer 2 d
Since we have 2 numbers, we'll be square rooting.
All we have to do to find the mean is multiply & square root the products.
30 × 6 = 180

You can use the same process and check my answer if you'd like; I rounded the square root, so you may get a different answer.