Which element must be present in an organic compound? (1) hydrogen (3) carbon(2) oxygen (4) nitrogen

the answer is 3) carbon

main component of organic compounds are the element carbon

C forms covalent compounds with other C atoms and form long chains resulting in forming compounds that are very useful to us in our day to day life

human body is made of 4 types of organic molecules.

C covalently bonds with other atoms such as H, O and N etc. forming a large array of useful compounds

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.

they both have a y in them