Is it true that during the civil war the north’s economy experienced major growth

Yes, it is true that the North’s economy experienced major growth during the civil war  

Explanation:  

The American economy entered into the eve of the civil war. The North, unlike the South, was good by its way to trade and a productive economy. These would have an impact directly on its ability to fight. By 1860, 90% of the country's production came from the Northern states.

It produces 17 times cotton and woolen fabrics than the South. In addition, 30 times increased leather goods, 32 times firearms, and 20 times pig iron. North produced 3200 firearms out of 100 manufactured in the south. In 1860, only about 40% worked in agriculture when compared to 84% South population.  

d. the polar jet stream   lies between the polar easterlies and trade winds should be your answer