Could anyone please help me with Q2 is the subject "work" or "master artists"

Three important things a musician must do for a superior performance. essay

Luminous objects such as flashlights emit light that we can see. how do we see an object that isn’t luminous? a. the object emits light that reaches our eyes. b. light reflects off the object and reaches our eyes. c. light passes through the object uninterrupted. d. light is fully absorbed by the object. e. we can’t see an object that isn’t luminous.

What does it mean when the bisecyer of the photosynthesis of the root of 27 equals 3