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Required informetion

Sometimes equations can be developed and practical problems solved by knowing nothing more than the dimensions of the key parameters. For example, consider the heat loss through a window in a building. Window efficiency is rated in terms of $R$ value, which has the unit of $f{t}^2*hr.\frac{}{?}$ Btu. A certain manufacturer offers a double$-$pane window with $R=2\mathrm{.}5$ and also a triple$-$pane window with $R=3\mathrm{.}4.$ Both windows are $6$ ft by $5\mathrm{.}25$ ft $.$ On a given winter day the temperature difference between the inside and outside is $45F.$

Develop an equation for window heat loss $Q$ in time period $t$ as a function of window area $A,R$ value, and temperature difference $T.$

Multiple Choice

$Q=tT\frac{A}{R}$

$Q=T\frac{A}{R}t$

$Q=tTA{R}^2$

$Q=tAIT{R}^2$