Energy 1. Stored energy or energy due to position is known as
2. The formula for calculating potential energy is
3. The three things that determine the amount of potential energy are (see equation above)
and

the answer to your question is c.

if you read the house of usher you should know that the house was haunted

the density(ratio between mass and volume as m/v) decreases from top to bottom in periodic table group as the size increases and nuclear charge decreases. but in periods density increases from left to right as atom size decreases and nuclear charge increases.