Step-by-step explanation:
so, that means we want to find the time t (days) after which N = No/2
because "half-life" means the amount of time until half of the substance has disappeared (or transformed into something else).
so, we have
No/2 = No × e^(-0.1481×t)
No = 2× No × e^(-0.1481×t)
1 = 2×e^(‐0.1481×t)
1/2 = 0.5 = e^(-0.1481×t)
ln(0.5) = -0.1481×t
t = ln(0.5)/-0.1481 = 4.680264555... ≈ 4.7 days
P = the money, so...
20 - ( 4 times 3)
20 - 12
8. She has $8 remaining. Hope it helps! I you could vote me brainliest, that would be awesome!
Answer:
Every week, the radioactivity decreases by a factor of 5
After 1 week, it goes from 5,000 to 1,000
2 weeks 1,000 / 5 =200
3 weeks 200 / 5 = 40
4 weeks 40 / 5 = 8
5 weeks 8 / 5 = 1.6
6 weeks 1.6 / 5 = 0.064
7 weeks 0.064 / 5 = 0.0128
8 weeks .0128 / 5 = 0.00256
9 weeks 0.00256 / 5 = 0.000512
10 weeks 0.000512 / 5 = 0.0001024
Step-by-step explanation:
5•2•5)-2 2
10•5)-2 2
50-2 2
48•2
96
So the answer is 96
I hope this helps you. The answer is c