Question

3) The modern periodic table has.
horizontal rows which are called
as
4) The age of rocks and fossils can be determined with the help of
isotopes.​

Answer 1

Answer:

3) period because A period is a horizontal row of the periodic table. A group is a vertical row of the periodic table

4) the age of rocks and fossils in number of years could be determined through radiometric age dating.

Explanation:

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