What is the respective ratio between the total number of tourists in city A in April and May together and that in city B in the same months together

What is the average number of tourists in city A in February and March

What is the difference between total number of tourists in cities A and B together in January and that in February

In the month of December of the previous year (2004) , the total number of tourists in both the cities together were 25% more than that in January 2005. What was the number of tourists in both the cities together in December 2004

Number of tourists in City B in April are what precent more than that in City A in the same month 

A jar has 60 litre milk. From the jar, 12 litre of milk was taken out and replaced by an equal amount of water. If 12 litre of the newly formed mixture is taken out of the jar, what is the final quantity of milk left in the jar