Answer:
We have 197 g of Co-60 after 18 months.
Step-by-step explanation:
We can use the decay equation.

Where:
- M(f) and M(i) are the final and initial mass respectively
- λ is the decay constant (ln(2)/t(1/2))
- t(1/2) is the half-life of Co
- t is the time at the final amount of m
<u>Therefore, we have 197 g of Co-60 after 18 months.</u>
I hope it helps you!
Answer:
16
Step-by-step explanation:
To solve, we can use an equation finding the average of the siblings'ages.

7x2.2 is 14.4 then you will need to multiply 3x2.2 then add them up
Four scarves and six hats is $52.00
<span>4s+6h=52 </span>
<span>two hats is $1.00 more than the cost of one scarf. </span>
<span>2h=1s+1 </span>
<span>2h=s+1 </span>
<span>s=2h-1 </span>
<span>substitute for s </span>
<span>4s+6h=52 </span>
<span>4(2h-1)+6h=52 </span>
<span>8h-4+6h=52 </span>
<span>14h=56 </span>
<span>h=4 </span>
<span>s=2h-1 </span>
<span>s=8-1 </span>
<span>s=7 </span>
<span>a scarf cost $7 </span>
<span>a hat cost $4</span>