Please give me the answers to all you can.

Match each object to its description: a. coma of a comet b. comet tail c. oort cloud haze surrounding a nucleus created by solar wind. hypothetical sphere around the solar system

This is a characteristic of the elements in the periodic table that shows a pattern. it may increase or decrease across or down the table.

Consider the elements bromine and chlorine; which elements has a larger ionic radius ?