A particular exosolar system has five planets in total: A, B, C, D, and E. The table lists the orbital periods of these planets in days. Planet Orbital Period (Days) A 600 B 80 C 1,000 D 500 E 100

(moving out from the center)

First layer: B

Second layer: E

Third layer: D

Fourth layer: A

Fifth layer: C

Due to their polarity, water molecules attract each other. The positive (+ve) end (a hydrogen atom) of one water molecule forms a hydrogen bond, a weak bond with the negative (-ve) end (an oxygen atom) atom of another water molecule. Due hydrogen bonds water have many of its unique qualities such as solvent properties of water.