JAVA:

Each month has 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31 days respectively. Show the average number of days for the 12 months.

Read in integers until the user enters -1. If there was at least one integer, show the average value. If there is less than one integer, print nothing.

Read in characters until the user enters a full stop '.'. Show the number of lowercase vowels.

Read in integers until the user enters -1. If there were at least 3 values, show the average excluding the biggest and smallest number. If there are less than 3 values, print nothing.