What is the mass percent of oxygen in sodium bicarbonate (nahco3)? 19.04% 27.37% 38.09% 57.13%

Na- 11=22

H-1 =1

C-12=12

O3=16*3 =48

total = 22+1+12+48 = 83

83> 48

100> 100*48/83=57.83 = 57.13 is nearest answer

the positions which points up in upward carbon and down in downward carbon are axial

and vice versa holds true for equatorial positions

so the correct answer with labelled diagram will be

it should have an internal chamber and two thermometers sticking out of the top. the internal chamber will also be closed off from the outside.