Three students test the effects of fertilizer on bean plant growth

abraham lincoln issued the preliminary emancipation proclamation on september 22nd, 1862. it stipulated that if the southern states did not cease their rebellion by january 1st, 1863, then proclamation would go into effect.

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.

i think it is the third one.