Professor Tom Cowing conducted a study on the time his students spent studying for his course. The study showed that the students spent an average of 2.3 hours studying, with a standard deviation of 0.50 hours and it follows the normal probability distribution.
A) Find the portion of the students who were studying between 2.3 and 3 hours.
B) Find the portion of the students who were studying more than 3 hours.
C) Find the portion of the students who were studying between 3 and 3.5 hours.
D) Find the portion of the students who were studying between 2 and 3.5 hours.