Hello!
A sample of Bromine-82 begins at 80 mL. We are given that this value will decrease by half of its current amount every 35 hours. First, we'll determine the number of times that 35 goes into 140. This will reveal the number of times we should divide the sample by 2:
140 ÷ 35 = 4
We have now proven that there are 4 periods of 35 hours in 140 hours. This means that we will divide the sample in half a total of 4 times, as follows:
1. 80 ÷ 2 = 40
2. 40 ÷ 2 = 20
3. 20 ÷ 2 = 10
4. 10 ÷ 2 = 5
We have now proven that an 80 mL sample of Bromine-82 will be reduced to only 5 mL after 140 hours. Therefore, the correct answer is 5 mL.
I hope this helps!
Answer:
Step-by-step explanation:
I think it’s B I’m sorry if I’m wrong
9514 1404 393
Answer:
6. A
7. C
8. E
Step-by-step explanation:
6. Devon gets $0.45 for each of the s programs he sells, so his pay for selling is 0.45s. He gets a $40 flat rate for each game, so his total pay is ...
p = 0.45s + 40 . . . . . matches choice A
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7. Robert gets $25 per hour in tips for each of the x hours he works, so his tip earnings are 25x. He gets a $40 flat rate for each day he works, so his total pay for working x hours is ...
y = 25x +40 . . . . . matches choice C
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8. The graph of a proportional relationship is a straight line through the origin. This is described by B and C, so choice E is the best.