As the hypothesis of sea-floor spreading predicts, the age of the ocean floor differs with location. what pattern does the ocean floor’s age form?

According to the loco mass the mass of reactants and products

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).

Which label correctly identifies what x represents in the concept map?