Which term describes a pattern in which rapid changes occur in a species for short period, followed by a long period of little or no change?

a. artificial selection
b. gradualism
c. extinction
d. punctuated equilibrium

propane is burned to provide the heat in many cooking grills. the chemical reaction for this process is shown in the equation below.

c3h8 + 5o2 ? 3 co2 + 4h2o + energy

what are the products in this chemical reaction?

3co2 + 4h2o + energy

answer; ///animal spirits;