Can you show me the whole solution ?
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Start by writing down the formula for surface area of a sphere: A = 4pi*r^2.
A hemisphere is half a sphere, so take half of that. A = 2pi * r^2.
Are you supposed to include the flat side? That's a circle with the same radius, A = pi*r^2.
So the total is now A = 3pi*r^2.
Now plug in r, which you know because you know the diameter.
A hemisphere is half a sphere, so take half of that. A = 2pi * r^2.
Are you supposed to include the flat side? That's a circle with the same radius, A = pi*r^2.
So the total is now A = 3pi*r^2.
Now plug in r, which you know because you know the diameter.