Seriously Sam....you have posted 14 questions...have you TRIED to answer ANY of them? Or are you just wanting answers to your homework? Why don't you TRY to answer some and see what you get? THEN ask a question !
This one:
tan x = sin x /cos x cos and sin at pi + x are just the negative of cos (x) and sin (x)
tan (pi +x) = sin (pi +x) / cos(pi + x) = -sin(x) / -cos(x) = sin(x)/ cos(x) = 2/5
I'll answer more of your questions after I see your attempts at answers.....Have a good night !