Question Number 168388 by leicianocosta last updated on 09/Apr/22
Answered by Tibo last updated on 09/Apr/22
$$\left.{a}\right)\:\:\pi{r}^{\mathrm{2}} =\pi×\mathrm{9}\approx\mathrm{28}.\mathrm{26}{cm}^{\mathrm{2}} \\ $$$$\left.{b}\right)\:\:\mathrm{2}\pi{rh}=\mathrm{2}×\pi×\mathrm{3}×\mathrm{8}\approx\mathrm{150}.\mathrm{72}{cm}^{\mathrm{2}} \\ $$$$\left.{c}\right)\:\:\mathrm{2}\left(\mathrm{28}.\mathrm{26}\right)+\mathrm{150}.\mathrm{72}=\mathrm{297}.\mathrm{24}{cm}^{\mathrm{2}} \\ $$$$\left.{d}\right)\:\:\pi{r}^{\mathrm{2}} {h}=\pi×\mathrm{9}×\mathrm{8}\approx\mathrm{226}.\mathrm{08}{cm}^{\mathrm{3}} \\ $$$$ \\ $$