Riddle #3 - Discover the light switch

A windowless room contains three identical light bulbs.

Each light is connected to one of three switches outside of the room.

Each bulb is switched off at present.

You are outside the room, and the door is closed

Before opening the door you may play around with the light switches as many times as you like. But once you've opened the door, you may no longer touch a switch.

After this, you go into the room and examine the lights.

How can you tell which switch goes to which light?

Riddle #2 - What animal is it?

What animal has four legs in the morning, two legs at noon and three legs in the evening?

Riddle #1 - My Age

When my sister was born,  my father had five times my age. Last year, he had four times my age. When my sister will have double the age she has today, my father will have the triple of my age. What is my age?