A light ray bounces off a fish in your aquarium. It travels through the water, into the glass side of the aquarium, and
then into air. As the light from the glass hits the air, the index of
refraction for air is much
than the index of refraction
for glass which causes the light to bend toward the angle that it
entered the air.

Correct

Explanation:

Because the light can't travel as quickly in the water as it does in the air, the light bends around the pencil, causing it to look bent in the water. Basically, the light refraction gives the pencil a slight magnifying effect, which makes the angle appear bigger than it actually is, causing the pencil to look crooked.

500N

Explanation:

Basically the weight of water displaced is the amount of upthrust. The upthrust is equal to the weight of the water moved by the submerged part of the body and therefore is equal to 500N.

Hope this helps!