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A wooden article was made by scooping out a hemisphere from each end of a solid cylinder, as shown in the figure. If the height of the cylinder is $10$ cm and its base is of radius $3.5$ cm, find the total surface area of the article.
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Height of cylinder = $10$ cm
Radius of cylinder = radius of hemisphere = $3.5 = \frac{7}{2}$ cm
Total surface area of the article
= CSA of cylinder + CSA of $2$ hemispheres
= $$\begin{aligned}& 2\pi rh + 2 \times 2\pi r^2 \\ & = 2\pi r(h + 2r) \\ & = 2 \times \frac{22}{7} \times \frac{7}{2} (10 + 2 \times \frac{7}{2}) \\ & = 22 \times 17 = 374\end{aligned}$$ cm$^2$
Radius of cylinder = radius of hemisphere = $3.5 = \frac{7}{2}$ cm
Total surface area of the article
= CSA of cylinder + CSA of $2$ hemispheres
= $$\begin{aligned}& 2\pi rh + 2 \times 2\pi r^2 \\ & = 2\pi r(h + 2r) \\ & = 2 \times \frac{22}{7} \times \frac{7}{2} (10 + 2 \times \frac{7}{2}) \\ & = 22 \times 17 = 374\end{aligned}$$ cm$^2$