Answer:
If I am not wrong I think the answer is the last one
Step-by-step explanation:
For this case we have that by definition, the surface area of a cylinder is given by:
![SA = 2 \pi * r * h + 2 \pi * r ^ 2](https://tex.z-dn.net/?f=SA%20%3D%202%20%5Cpi%20%2A%20r%20%2A%20h%20%2B%202%20%5Cpi%20%2A%20r%20%5E%202)
Where:
r: It's the radio
h: It's the height
Substituting according to the data we have:
![SA = 2 \pi * (38) * (51) +2 \pi * (38) ^ 2\\SA = 2 \pi * 1938 + 2 \pi * 1444\\SA = 3876 \pi + 2888 \pi\\SA = 6764 \pi](https://tex.z-dn.net/?f=SA%20%3D%202%20%5Cpi%20%2A%20%2838%29%20%2A%20%2851%29%20%2B2%20%5Cpi%20%2A%20%2838%29%20%5E%202%5C%5CSA%20%3D%202%20%5Cpi%20%2A%201938%20%2B%202%20%5Cpi%20%2A%201444%5C%5CSA%20%3D%203876%20%5Cpi%20%2B%202888%20%5Cpi%5C%5CSA%20%3D%206764%20%5Cpi)
Thus, the surface area of the cylinder is ![6764 \pi \ mm ^ 2](https://tex.z-dn.net/?f=6764%20%5Cpi%20%5C%20mm%20%5E%202)
Answer:
![6764 \pi \ mm ^ 2](https://tex.z-dn.net/?f=6764%20%5Cpi%20%5C%20mm%20%5E%202)
Each child has a 50% chance to be a girl and 50%chance to be a boy so with 4 children the probability is