Steve’s Intro Psych instructor collects homework assignments after every class. There are periods when she awards extra credit after every assignment; at other times, five assignments will go by without extra credit. To increase his chances of getting the extra points, Steve consistently turns in the homework. Steve is reinforced on a – schedule.

variable-ratio

Explanation:

two jet streams that directly affect the formation of weather in the continental part are a polar jet and a subtropical jet. they are responsible for the transportation of weather systems, which directly affect people. the polar front is the boundary between cold air from the north pole and warmer equatorial air. both the polar jet and the subtropical jet blow from the west to the east, and follow the boundary between cold and warm air.

the strongest jet streams are polar jets, while subtropical jets are somewhat weaker.

the right answer is c. the polar jet stream is generaly stronger than the subtropical jet stream.

haile selassie i was the emperor of ethiopia from 1930-1974