no it does not
Straight line.
yes
true
Light is a particle that acts like a wave and therefore does not travel in a straight line. light has nothing to do with gravity, the fourth dimension or the 'fabric' of space time.
light travels in a straight line because it can only be bend by reflective objects.
Yes because, Light travels in a straight path called a light ray.
There are more things for the light waves to bounce off of in water, so light can not travel in a straight line or as far.
travels through a uniform medium
Because light rays travel in straight line just like a ruler/scale. We can represent it with anything which is straight like a ruler...
Normal. It takes a lot of mass to bend light.
Normally light travels in a straight line. However, it has been demonstrated that gravity can bend the path of light.