The average number of acres burned by forest and range fires in a large county is 3,800 acres per year, with a standard deviation of 700 acres. If the distribution of the number of acres burned is normal, what is the probability that the number of acres burned is between 2,800 and 4,600 acres?
a) 0.6368
b) 0.8186
c) 0.9545
d) 0.9973