Which of the following is an example of a renewable resource
a. iron
b. petroleum
c. energy from flowing water
d. coal

answer; people have no objective standard by which to judge themselves;

answer; the automatic system because it is a "gut reactor"  

answer; the sound of a train whistle makes a woman think of an old friend; //

the smell of grass makes a by feel that spring is the best; (apex);

answer; differentiation;