To balance an equation, what should you never change?

To balance a chemical equation, you can't change the subscripts. If you change or mess around with the subscripts, you may be balancing the equation but it's no longer the equation that you are are dealing with.

So as a rule, you can't modify any of the subscripts.

answer: the figure is attached herewith.

step-by-step explanation:   we are given to sketch a unit circle and label the terminal points corresponding to

in the attached figure, we have drawn a unit circle, with centre at o(0,0) and radius 1 unit. we have labelled the points a, b, c, d and e corresponding to the angles below

∠aox = 60°,

∠box = 120°,

∠cox = 180°,

∠dox = 240°,

∠eox = 300°.

and the coordinates are a(0.5,1), b(-0.5,1), c(-1,0), d(-0.5,-1) and e(0.5,-1).

thus, the answer is complete.