Which invention made the building and use of skyscrapers feasible?
a. mass transit c. zoning laws
b. elevators d. suburbs

The answer to this question is B. Elevators
One of the reason why skyscrapers were not popular before the invention of elevators was that it took too much energy to move from the groud floor to the upper floor with the stairs alone.
After the invention of elevators, we eliminate this problem and people could move from ground floor to upper floor with only little effort.

Taking a shower. why is cause as you shower the water is running more than taking a bath, washing a load of dishes or brushing your teeth. water is being used more by taking a shower and depending on how many people live in the household that take showers. some take a shower twice a day.

Ithink it's c selection but i don't really know.