8. The weights of another type of chocolate bar are also Normally distributed. On the wrapper it states that the bar weighs 25 grams. It is known that 99% of these bars weigh at least 25.0 grams and 75% of them weigh at least 25.4 grams.

a) Find the probability that one of these bars weighs at least 26.0 grams.

b) One bar of the first type (from Q7) and 2 bars of the second type (Q8) are selected at random. Find the probability that at least one of the bars has a weight less than that stated on its wrapper.