The value of sin (pi/6) is 1/2
The first step is to multiply the fraction by (3 +3i) / (3 +3i) to delete the i terms from the denominator:

506,211+424,809=931,020 sum means add hope this helps
Answer:
Step-by-step explanation:
There is one large case with 20 cars and 3 small cases with n cars in each.
<u>Possible number of cars C is:</u>
The amount of the radioactive material in the vault after 140 years is 210 pounds
<h3>How to determine the amount</h3>
We have that the function is given as a model;
f(x) = 300(0.5)x/100
Where
- x = number of years of the vault = 140 years
- f(x) is the amount in pounds
Let's substitute the value of 'x' in the model
f(x) = 300(0.5)x/100


f(140) = 210 pounds
This mean that the function of 149 years would give an amount of 210 pounds rounded up to the nearest whole number.
Thus, the amount of the radioactive material in the vault after 140 years is 210 pounds
Learn more amount radioactive decay here:
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