Standard Delivery Service provides next day delivery of packages weighing between 2 and 12 pounds in an Ohio city. They have found that the weights of the packages they deliver are normally distributed with mean 7 pounds and standard deviation 1.2 pounds.

What is the probability that a package weighs between 5.5 and 9 pounds?

a)0.8944

b)0.9522

c)0.1056

d)0.8466