The concentration of lithium chlorite solution is 12.0% by mass. In a ___g sample of this solution, there are 238.5g of dissolved lithium chlorate. Answer is A) 1990 but I do not know to go to there please help!

Mass of sample : 1987.5 g≈1990 g

Given

12% mass of Lithium chlorate

Required

Mass of sample

Solution

%mass = (mass of solute/mass of solution) x 100%

mass of solute = mass of Lithium chlorate = 238.5 g

Input the value :

12/100(0.12) = 238.5 g : mass of solution

mass of solution =238.5 : 0.12

mass of solution = 1987.5≈1990 g

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.