Science is painful I will give brainily to the correct answer :D

In dna, only the_ varies from one nucleotide to another. base phosphate sugar amino acid

Draw the farm's ppf for corn and beef. draw a point that shows an inefficient combination of corn and beef. label ita. draw a point that shows an unattainable combination of corn and beef. label itb. draw a point that shows an efficient combination of corn and beef. label itc.

Pl as time goes by and water goes through the water cycle again and again, the amount of water on earth: increases decreases ostays the same goes up and down