Which element is considered to be a transition element?
F
Sn
Cu
Na

Cu

Explanation:

From the given choices only Copper is considered a transition element.

Transition elements are found between the groups IIIB - IIB on the periodic table.

These elements are also said to be d-block elements.

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