During mendel's first set of experiments, he allowed true-breeding tall plants
to cross with true-breeding short plants. what happened when he allowed the
f, offspring from this first set of experiments to self-pollinate?

Explanation:

What Mendel wanted to happen was to obtain middle-sized plants. What actually happened was that Mendel got tall plants. Due to this result, Mendel called Reccesive to the genes thatdetermined the short offspring, and Dominant to the genes that determined the tall offspring.

they had the law tat factories that produces smoke cannot be built near residential buildings.

building of proper sewage system was done to ensure that the waste is carried away from the humans so that they do not get diseases from it.

also they built water systems to provide water in those areas which are drought prone.