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!
The distance, In feet, from the base of the ladder to the base of the wall is 4.2 ft.
He needs to move the ladder 0.1 ft closer to the base of the building.
The situation forms a right angle triangle.
<h3>Right angle triangle</h3>
Right angle triangle has one of its angles as 90 degrees. The sides and angle can be found using trigonometric ratios.
The length of the ladder is the hypotenuse of the triangle formed. Therefore, the distance, In feet, from the base of the ladder to the base of the wall can be calculated as follows;
cos 65° = adjacent / hypotenuse
cos 65° = d / 10
d = 10 × 0.42261826174
d = 4.22618261741
d = 4.2 ft
She needs to move the ladder so it reached a window 9.6 feet above the ground. Therefore, the distance from the base of the ladder and the wall is as follows;
cos 65 = d / 9.6
d = 9.6 × 0.42261826174
d = 4.05696
d = 4.1
Therefore, he needs to move the ladder 0.1 ft closer to the building.
learn more on right angle triangle here: brainly.com/question/14988069
Answer: wt-
Step-by-step explanation: hehe
A=27.18
There is a photo showing the answer and the formula and stuff hope this helps