From 100 homes of similar sizes, sample of 25 homes is chosen to study the average home heating cost throughout the winter months. Assume the heating cost is known to be normally distributed with mean of $220 per month for four months of winter and standard deviation of $45. If the 100 homes represents the population size, the standard error of the heating cost would be:
(a) 9.00
(b) 8.75
(c) 3.66
(d) 7.83
(e) 1.87