Which word best describes the mood in much of the world as the cold war ended angry optimistic cautious worried?

Ascientist performs an experiment where she measures the mass of a piece of metal, pours acid onto the metal, washes the metal, and then re-measures the mass of the metal. the scientist repeats the experiment several times, each time increasing the amount of acid used. the dependent variable in the experiment is the: initial mass of the metal final mass of the metal amount of acid used washing the metal

What emperor was given credit for having the aqueducts built

What something thats on the news, and is going on currently?