British thermal unit

\[\begin{aligned} y[Joule] &= 1055.06x[British\ thermal\ unit] \\ y[Kilojoule] &= 1.05506x \\ y[gram\text{-}calorie] &= 252.164x \\ y[Kilocalorie] &= 0.252164x \\ y[Watt\ hour] &= 0.293071x \\ y[Kilowatt\ hour] &= 0.000293071x \\ y[Electronvolt] &= 6.585 \times 10^{21}x \\ y[US\ therm] &= 1.0002 \times 10^{-5}x \\ y[foot\ pound] &= 778.169x \end{aligned}\]