User blog:Wildoneshelper/I question you... (Episode 8) (How can I know?)

I question you is back! This time I'm going to ask you some questions:


 * 1) How do I know if I'm a hacker?
 * 2) How do I know if this substance is zinc bromide?
 * 3) How do I know if sin(270°+θ)/cos(90°+θ) is identical to sin(270°-θ)/cos(90°-θ)? Is sin(360°+θ)/cos(180°+θ) also identical to sin(360°-θ)/cos(180°-θ)?
 * 4) How do I know if g=9.81..............
 * 5) How do I know if I love studying or not?