What is the name of group 6a,7a, and 8a

How many moles are in 7.2 x 10^23 carbon molecules? (*round to the nearest hundredth and include the unit "mol c" after your number) question 6 options:

An atom of lithium-7 has an equal number of(1) electrons and neutrons(2) electrons and protons(3) positrons and neutrons(4) positrons and protons

Jose and eric were given four samples in lab. the results of their analysis are shown in the table. based on the data they collected, which sample is most likely a metal?