A) \[3300\,c{{m}^{2}}\]
B) \[1914\,\,c{{m}^{2}}\]
C) \[2564\,c{{m}^{2}}\]
D) None of these
Correct Answer: A
Solution :
\[r=21\,cm,\] \[h=20\,cm\] \[\therefore \] \[l=\sqrt{{{h}^{2}}+{{r}^{2}}}=29\,\,cm\] \[\therefore \] Area of the sheet = Total surface of the cone \[=\pi rl+\pi {{r}^{2}}\] \[=\pi r(l+r)=\frac{22}{7}\times 21(29+21)\] \[=3300\,\,c{{m}^{2}}\]You need to login to perform this action.
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