In a certain city, 5% of all the persons in town have unlisted phone numbers. If you select 100 names at random from that city's phone directory, how many people selected will have unlisted phone numbers?
The elements in the same column will have similar properties. Beryllium is the group II element. Group II elements are magnesium, calcium, strontium, barium and radium. Hence, these show the similar prperties.