Logical Puzzles - General Questions

A lily pad doubles in size every day and covers a pond in 30 days. On which day was the pond half covered?

A man has 3 daughters. Each daughter has one brother. How many children does he have?

A snail climbs 3 m up a 10 m wall each day and slips back 2 m each night. On which day does it reach the top?

If 3 cats catch 3 mice in 3 minutes, how many cats are needed to catch 100 mice in 100 minutes?

How many months have 28 days?