Answer:
Selenium is a semiconductor
Explanation:
Selenium is a semiconductor.
Elements in the column IV and VI of the periodic table are referred to as Semiconductor.
Selenium lies in the column VI along with Tellurium
Some other elements of the column IV are silicon, germanium, and tin
To find the answer, plot down the factors for every number.
12: 1, 2 ,3 ,4, 6, 12
18: 1, 2, 3, 6, 9, 18
84: 1, 2, 3, 4, 6, 7, 12
If you noticed, the number that was common to the 3 numbers, were 1, 2, 3, and 6
And 6 is the bigger number
So 6 is your GCF
