Choose the items that demonstrate potential energy. Train leaving the station, gallon of gasoline, rock sitting at the top of a cliff, sleeping dog, stopped car

gallon of gasoline

rock sitting at the top of a cliff

sleeping dog

stopped car

Explanation:

Potential energy is defined as the stored energy that an object has because of its position or shape. It is impossible to observe this energy's effects until this energy is released and transformed into some form of energy. We have two types of potential energy:

Gravitational potential energy: We can define gravitational potential energy as energy stored by a gain in height that an object makes.

Elastic potential energy: Elastic potential energy is defined as the energy stored in elastic objects (springs, rubber bands) when compressed or stretched from their natural position.

From the list of the options given: gallon of gasoline, rock sitting at the top of a cliff, sleeping dog and stopped car are all potential energy.

i think it's letter a.

answer: atomic mass was originally used to arrange elements on the periodic table, but is no longer used to organize the modern version.

explanation:

originally atomic mass was used to arrange elements on the periodic table from left to right in a row. each column then shows similar properties of elements of a group.

in modern periodic table, the atoms are arranged in increasing atomic number. as atomic number represents the number of protons in an atom which is unique for every atom.