14.the element above is a(n): a helium atom b lithium atom c beryllium atom d beryllium isotope 15.this atom's charge is a +4 b -4 c neutral d not enough info given 16.this atom has an atomic mass of __ and an atomic number of __ a 12, 8 b 4, 8 c 8, 4 d 4, 4

1. variations in a population of moths allow for some of its members to be able to adapt to environmental changes. the better adapted of the moths will be able to survive the change and thus prevail as the “fittest” of the species. (a) describe three mechanisms in which variation can occur within a species population. (b) explain which mechanism or mechanisms would be responsible for the survival of a population of peppered moths better than white moths in an environment affected by industrial soot. justify your answer.