The use of brushes most likely means that this is a:

A: DC MOTOR
B: AC MOTOR

lower, it's not as dense as chocolate syrup.

choco syrup is more like a solid than a liquid and even turns solid if it gets slightly cold,

orange juice however is a 95% liquid and has a very low viscosity

a straight line sloped

luster is not a good characteristic to use by itself because luster is the property of minerals that indicates how much the surface of a mineral reflects light. the luster of a mineral is affected by the brilliance of the light used to observe the mineral surface.

i think its c if i'm wrong