I only have a question about how to get a negative -1 above the sin, cos, tan?

arc sine is the same as inverse sine so on the web2.0 calc you just press

[2nd] [asin]  340

Make sure the toggle on the bottom left is set to degrees.

OR

if you press [sin] and leave your finger on it for a little longer than normal it will automatically turn into asin  :)

But the arcsine of 340 doesn't make sense (sine has to be between -1 and +1) so it's possible here the question is asking how to calculate sin(340°)^-1 or 1/sin(340°).  This can be done either by typing in 1/sin(340) or sin(340)^-1 and pressing = or Enter.