Answer:
24 hours
Step-by-step explanation:
One member of the gardening club can alone plant flowers in 12 hours.
So in 1 hour he can plant 1/12 of the flowers.
Let the time required by the second member of the club to plant flowers alone be x hours.
Then in 1 hour he can plant 1/x of the flowers.
Now when the two members work together,each hour they can plant:
of the flowers.
But they can together complete the job in 8 hours. So in one hour they plant 1/8 of the flowers.
=> ![\[\frac{1}{12}+\frac{1}{x}=\frac{1}{8}\]](https://tex.z-dn.net/?f=%5C%5B%5Cfrac%7B1%7D%7B12%7D%2B%5Cfrac%7B1%7D%7Bx%7D%3D%5Cfrac%7B1%7D%7B8%7D%5C%5D)
=> ![\[\frac{1}{x}=\frac{1}{24}\] ](https://tex.z-dn.net/?f=%5C%5B%5Cfrac%7B1%7D%7Bx%7D%3D%5Cfrac%7B1%7D%7B24%7D%5C%5D%0A)
=> x=24
So the second member can plant the flowers alone in 24 hours
Answer: 
Step-by-step explanation:
1. If you join the top part and the bottom part of the figure, you obtain a sphere. Then, you must apply the formula for calculate the surface area of a sphere:

Where r is the radius (
)
2. Then:

3. The formula for calculate the suface area of the red part, which is a cylinder, is:

Where h is the height (h=32mm)
4. Then:

5. So, the total surface area is:
