Think about all of the inventions you’ve discovered in this lesson. Which two inventions changed Americans’ lives the most?

Electricity and the light bulb. The electricity because thanks to the invention many people were able to communicate more and it was first used for so many other inventions on the way. The light bulb  became VERY important and especially for everyday convenience since the invention around 1802..it is said that there's about 20 light bulb inventors (Thomas Edison was just credited). steam power and electricity as well.

i believe your answer is d)

john maynard keynes developed new economic theories in response to the : b) great depression of the 1930s. his theories are so important that they are known as "keynesianism". in his works he supports the idea of a government with deeper involvement and intervention to end the great depression.