In the dna double helix, how are the two strands of dna held together?

Flock x flock y flock z total pieces of food eaten (from previous page) 147 93 60 food percentage* % % % simulated number of birds in flock for 3rd generation** * divide each flock's total pieces of food by 300, the total number of pieces of food eaten. ** multiply the food percentage for each flock by the total number of birds (30).

Models are non-visual ways of coummincating how someone thinks about something in the natural world

In the water cycle , when does water undergo a chemical change