Confuse?

S years ago, Annie is R years old. How old is Annie T years later?

Just like the title, I wanna ask you: confuse reading this problem?
HAHAHAHAHAHAHAHAHAHAHAH!!!
So do I...

Why? Why? Why?

If Circle K is a 24-hour shop, why does it have a door key?

What is the temperature?

Weather forecast: "Temperature tomorrow will be twice hotter than today"

If today's temperature is 4 Celsius, temperature tomorrow is 8 Celsius, because, 4 x 2 = 8.
If today's temperature is 2 Celsius, temperature tomorrow is 4 Celsius, because, 2 x 2 = 4.
If today's temperature is 0 Celsius, what is the temperature tomorrow?

Solve This!

Good luck ;)