First required to be found would be the radius, as you already have, is 5. Then use the formula 4 \pi r ^{2} [/tex], then you would receive the answer, for that would be 314.16.
Answer:
1
Step-by-step explanation:
1 goes into 1 one time so it = 1
Answer:
I don't know if this is what you meant, but it's a linear equation.
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:
Step-by-step explanation: