i) Area = $\frac{22}{7}r^2$ = $\frac{22}{7}\times 10^2 = 314 cm^2$
ii) Volume of one oil drop = volume of oil patch
6.54 $\times$ 10-5 = 314 $\times d$
d = 2.08 $\times$ 10-7 cm
johnmulu answered the question on February 9, 2017 at 09:51
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