The efficiency of a Carnot engine working between the temperatures \(T_{1}\) and \(T_{2}\) \(\left(T_{1}

(a) \(\frac{T_{2}-T_{1}}{T_{2}}\)

(b) \(\frac{T_{2}-T_{1}}{T_{1}}\)

(c) \(\frac{T_{1}-T_{2}}{T_{2}}\)

(d) \(\frac{T_{1}-T_{2}}{T_{1}}\).