The correct answer is (a.) a parsec. A parsec is a distance an object would be from Earth if its parallax were one arcsecond. This unit of measurement is usually used in astronomy which makes it easier for astronomers to calculate or measure in space accurately.
Answer:
1) D
2) A
Explanation:
1) Each group has the same number of valence electrons, which are the outer electrons.
2) Ionic bonds are between a metal and non - metal, the metal being sodium and the non - metal being chlorine.
Answer:it is 343 meter per second in air.
Explanation:
it is 5 times more in liquids than in gases and 15 times more in solids than in gases.In air it is affected by various physical conditions such as pressure,humidity and temperature.
Answer:
The "butterfly Effect"
Explanation:
The "butterfly effect" will probably have big changes in the future.
(31-15 = 16).
Explanation:
the element phosphorus (P) has an atomic number of 15 and a mass number of 31. Therefore, an atom of phosphorus has 15 protons, 15 electrons, and 16 neutrons
