4 Melons are sold in three sizes: small, medium and large. The weights follow a normal distribution with mean 450 grams and standard deviation 120 grams. Melons weighing less than 350 grams are classified as small.
- Find the proportion of melons which are classified as small.
- The rest of the melons are divided in equal proportions between medium and large. Find the weight above which melons are classified as large.