Answer:
Cd, Cr, Cu, Hg, Pb, and Zn
Explanation:
There are five main modes of seed dispersal: gravity, wind, ballistic, water, and by animals. Some plants are serotinous and only disperse their seeds in response to an environmental stimulus. Because plants cannot walk around and take their seeds to other places, they have developed other methods to disperse (move) their seeds. Dandelion seeds float away in the wind
