Atomic size

a. decreases as you move from top to bottom within a group

b. remains constant within a period

c. decreases as you move from left to right across a period

d. increases as you move from left to right across a period

Option C, decreases as you move from left to right across a period

As you move from left to right across a period, the atoms get more and more protons. These protons pull on the electrons, making the atoms progressively smaller and smaller because of the increasing pull.

8 carbon atoms forming single bonds with 18 hydrogen atoms; a triple bond exists between the third and fourth carbon atom from the right

explanation:

what is the average time it took the car to travel 0.25 meters?

⇒ 2.23 seconds

what is the average time it took the car to travel 0.50 meters?

⇒ 3.13 seconds