Are there more inches in a mile...

...or Sundays in a thousand years?

Which word does not belong with the others:

dgo act ehors ceffio elrttu ekmnoy

There is a closed room with a light in it. Outside, there are 3 light switches.

You can flick any of the switches any number of times.

You can only open the door and go into the room once.

You know that the light is initially off and you can't see what happens when you flick the switches.

How can you determine which light switch operates the light?

Yesterday my mother asked me to buy some stamps.

Stamps, in the land of BrainBashers, are available in 2p, 7p, 10p, 15p and 20p denominations.

For three types of stamp I was asked to buy five of each.

For the other two types of stamp, I was asked to buy six of each.

Unfortunately I forgot which I was supposed to buy five of and which to buy six of.

Luckily my mother had given me the exact money required to buy the stamps, £3.00 and the shopkeeper was able to give me the correct stamps.

Which stamps did I buy?