Hello,
The formula for finding the area of a circular region is:

then:

With the two radius it is formed an isosceles triangle, so, we must obtain its area, but first we obtain the height and the base.

Now we can find its area:
![A_{2}=2* \frac{b*h}{2} \\ \\ A_{2}= [r*sen(40)][r*cos(40)]\\ \\A_{2}= r^{2}*sen(40)*cos(40)](https://tex.z-dn.net/?f=A_%7B2%7D%3D2%2A%20%5Cfrac%7Bb%2Ah%7D%7B2%7D%20%20%5C%5C%20%20%5C%5C%20A_%7B2%7D%3D%20%5Br%2Asen%2840%29%5D%5Br%2Acos%2840%29%5D%5C%5C%20%20%5C%5CA_%7B2%7D%3D%20r%5E%7B2%7D%2Asen%2840%29%2Acos%2840%29)
The subtraction of the two areas is 100cm^2, then:
Answer: r= 1.59cm
Hello!
I would say the second option, because it looks like the most reasonable one. The third and fourth options decrease, but we can see by the chart that in fact, the weight increases. Also, it wouldn't be the first option, because its showing that the wight is always constant and rate doesn't change. However, we can see that this is wrong and the rate actually does change. Therefore, the second option looks like the most reasonable for this chart.
Hope this helps!
C 16 because a is 4 and 4 times 4 is equal to 16
The all go over 18 so put them all over 18
16/18+12/18+3/18=31/18
31/18 or 1.722222222........