Answer:
The time it takes light from a flash camera to reach a subject 6.0 meters across a room in scientific notation is 2.0 *10^-8 s.
The phrase which best describes a period on the periodic table is: a row of elements
Periodic table can be defined as an organized tabular arrangement of all the chemical elements arranged in order of increasing atomic number or number of protons, especially in rows.
On a related note, chemical elements with the same number of valence electrons are found in the same column of the periodic table.
In conclusion, the rows of a periodic table are referred to as periods while the columns are referred to as groups.
Read more: brainly.com/question/24441368
