Answer
In July
Work Step by Step
January:
$z=\frac{y-\mu}{\rho}$
$z=\frac{55-36}{10}=1.9$
July:
$z=\frac{y-\mu}{\rho}$
$z=\frac{55-74}{8}=-2.375$
The answer is in July because 55 F is further away from its mean than in January given that, in July, 55 F is 2.375 standard deviations below its mean and in January 55 F is 1.9 standard deviation above the mean.
