Answer
Please see the work below.
Work Step by Step
We know that
$e=1-\frac{T_c}{T_h}$
This can be rearranged as:
$T_c=T_h(1-e)$
We plug in the known values to obtain:
$T_c=(4.25)(1-0.777)$
$T_c=0.948K$
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