Answer:
A. Materials with a low index of refraction cause light to refract very little.
Answer: The density of this piece of jewelry is 
Explanation:
To calculate the density, we use the equation:

Mass of piece of jewellery = 130.8 g
Density of piece of jewellery = ?
Volume of piece of jewellery =( 62.4-47.7 ) ml = 14.7 ml =

Putting values in above equation, we get:

Thus density of this piece of jewelry is 
Answer:
Friction
Explanation:
Friction is a force that slows down moving objects. If you roll a ball across a shaggy rug, you can see that there are lumps and bumps in the rug that make the ball slow down. The rubbing, or friction, between the ball and the rug is what makes the ball stop rolling. External Force is required.
How can one explain<span> and predict the </span>interactions between objects<span> and within a system of </span>objects<span>? ... through </span>electric or magnetic fields to illustrate the forces between objects and the changes in energy of the objects due to the interaction<span>. ... </span>Forces<span> at a distance are </span>explained<span> by fields (gravitational, </span>electric<span>, and magnetic) ...</span>