Which of the following is a scientific way of building knowledge A. Common opinions
B. Lucky breaks
C. Empirical studies
D. Intuition

In addition to seeds, which of the following characteristics are unique to the seed-producing plants? a) sporopollenin b) lignin present in cell walls c) pollen d) use of air currents as a dispersal agent e) megaphylls

List the advantages and disadavantages of the switch from persistent chlorinated hydrocarbon pesticides (such as ddt) to nonpersistent organophosphate pesicides. have the benefits of the switch outweighed the disadvantages? explain.

Vinegar has a ph of 3, and household ammonia has a ph of 11. is the concentration of h+ greatest in the vinegar or ammonia?