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(C) The work done $W$ in blowing a soap bubble of radius $R$ is given by the formula $W = T 	imes \Delta A$,where $T$ is the surface tension and $\De

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$4W$

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(C) The work done $W$ in blowing a soap bubble of radius $R$ is given by the formula $W = T 	imes \Delta A$,where $T$ is the surface tension and $\Delta A$ is the change in surface area.Since a soap bubble has two surfaces (inner and outer),the surface area $A = 2 	imes (4\pi R^2) = 8\pi R^2$.Thus,$W = 8\pi R^2 T$.From this expression,we can see that $W \propto R^2$.If the radius is increased from $R$ to $2R$,the new work done $W'$ will be:$W' = 8\pi (2R)^2 T = 8\pi (4R^2) T = 4 	imes (8\pi R^2 T) = 4W$.Therefore,the work done becomes $4W$.

If work $W$ is done in blowing a bubble of radius $R$ from a soap solution,then the work done in blowing a bubble of radius $2R$ from the same solution is

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