Average speed is
a) a vector
b) the distance traveled divided by the time to travel that distance
c) measured in m/s
d) the slope of a velocity vs. time graph

I believe that the correct answer is choice B

each chemical family is represented as a group or column on the periodic table. based on chemical properties, there are 6 types of chemical families. group 1 represents alkali metals, group 2 represents alkaline earth metals, groups 3 to 12 represent transition metals, groups 13 to 16 represent non-metals and other metals, group 17 represents halogens and group 18 represents noble gases.