Answer:
i believe its A.4%
Step-by-step explanation:
it is correct
Step-by-step explanation:
Answer:
The mass of the radioactive sample after 40 minutes is 12.8 g.
Step-by-step explanation:
The mass of the sample can be found by using the exponential decay equation:

Where:
N(t): is the amount of the sample at time t =?
N₀: is the initial quantity of the sample = 120 g
t = 40 min
λ: is the decay constant = 0.056 min⁻¹
Hence, the mass of the sample after 40 min is:

Therefore, the mass of the radioactive sample after 40 minutes is 12.8 g.
I hope it helps you!
Answer:
Box A = 37.3333333333
Box B = 23.33333333333
Box C = 9.33333333333
Step-by-step explanation: