A 0.2kg apple on an apple tree has a potential energy of 10J. It falls to the ground, converting all of its PE to kinetic energy. What is the velocity of the apple just before it hits the ground? a. 0m/s
b. 2m/s
c. 10m/s
d. 50m/s

there is no correct list among the choices you've provided.

the list might look something like this:

-- baby human

-- piccolo

-- flute

-- soprano singer

-- trumpet

-- tenor singer

-- trombone

-- baritone singer

-- baritone horn

-- bass singer

-- tuba

since i had to make up the list myself, i made it easy on myself, and i didn't try to shuffle the string instruments and woodwinds into it too.

54 degrees incident angle = reflected angle

angle is from normal turned to line of ray