It is an Insulator I’m pretty sure
Answer:
b) the refracted ray has an angle of 90 degrees
Explanation:
The angle of incidence is measured with respect to the normal separation of the media. The critical angle for total internal reflection occurs is:
Here 
and 
are the refractive index of the mediums. This equation is an application of Snell's law, for the case where the refracted ray has an angle of 
.
The winter I think would be the answer
True, They contain old stars and posses little gas or dust
Sound waves travel faster through <em>solids</em> than they do through gases or liquids. <em>(C) </em>They don't travel through vacuum at all.
Example:
Speed of sound in normal air . . . around 340 m/s
Speed of sound in water . . . around 1,480 m/s
Speed of sound in iron . . . around 5,120 m/s
