Answer:
B. π/3
Step-by-step explanation:
I calculated it logically
Radioactive half-life is the time it takes for half an amount of radioactive material to decay into something else. In this case, it is assumed that the decay product is not radioactive or otherwise hazardous.
We must use the radioactive decay formula to determine at what time the radiation reaches a safe level.
A = Ao[e^(-0.693)(t)(t 1/2) where t 1/2 is the half-life, t is elapsed time, Ao is the original quantity, A is the future quantity.
We are given a half-life of 2.4 days , an Ao of 1.25 and an A of 1.00:
1.00 = (1.25)e^(-0.693)(2.4)t
1.00/1.25 = e^(-1.6632)t
0.8 = e^(-1.6632)t
t = 0.135 days = 3 hrs 15 min
This is the amount of time to a "safe level" using only radioactive decay, not venting or other means.
Answer:non proportional
Step-by-step explanation:
Answer:
1/3
Step-by-step explanation:
We are given ...
barrettes : hair ties = 5 : 7
barrettes : hair bands = 5 : 8
Then the combined ratios are ...
barrettes : hair ties : hair bands = 5 : 7 : 8
For every 5 barrettes, there are 7+8 = 15 hair ties and bands, so their ratio is ...
barrettes/(hair ties and bands) = 5/15 = 1/3
Answer:
A. 2 times the number of pages.
Step-by-step explanation:
We do not know the number of pages in A. 2 times the number of pages.
We know the number of years of schooling the number of seconds and the number of dollars and cents
B. 15 years of schooling. C. 60 seconds multiplied by 5. D. 3 dollars and 76 cents.