60 more squirrels is the answer because sine its an estimate, 91 turns into 90
therefore u have
90 squirrels and 1/3 as many chipmunks
1/3 of 90 is 30
90 - 30 = 60
Your answer is 60 more squirrels

8 0

3 years ago

Alexander Litvinenko was poisoned with 10 micrograms of the radioactive substance Polonium-210. Since radioactive decay follows

koban [17]

Answer:

The amount of Polonium-210 left in his body after 72 days is 6.937 μg.

Step-by-step explanation:

The decay rate of Polonium-210 is the following:

$N(t) = N_{0}e^{-\lambda t}$ (1)

Where:

N(t) is the quantity of Po-210 at time t =?

N₀ is the initial quantity of Po-210 = 10 μg

λ is the decay constant

t is the time = 72 d

The decay rate is 0.502%, hence the quantity that still remains in Alexander is 99.498%.

First, we need to find the decay constant:

$\lambda = \frac{ln(2)}{t_{1/2}}$ (2)

Where t(1/2) is the half-life of Po-210 = 138.376 days

By entering equation (2) into (1) we have:

$N(t) = N_{0}e^{-\frac{ln(2)}{t_{1/2}}*t}} = 10* \frac{99.498}{100}*e^{-\frac{ln(2)}{138.376}*72} = 6.937 \mu g$

Therefore, the amount of Polonium-210 left in his body after 72 days is 6.937 μg.

I hope it helps you!

8 0

3 years ago