According to the cladogram in figure 18-2, what two characteristics do crabs and barnacles share that limpets do not?

a=c and then d= c because of the band so you get ac/dc and you add them together you get sound waves

answerbacterium;

other quantities, called derived quantities, are defined in terms of the seven base quantities via a system of quantity equations. the si derived unitsfor these derived quantities are obtained from these equations and the seven si base units.