Anything can happen, everyday scientist are finding new electrons, metals, etc.
Over the next 50 years we could see way more metals, gas, etc.Knowing that anything can happen we would probaly see in increace.About 50 years ago our periodic table has less gas, etc on it.Back when the peridoc table was made there where barley any elements on it.There was a process of more elements beig added.You will never know when a new element will be added until they day it is.
The practice books I use to study for AP exams are 5 Steps to a 5, Barron's, the Princeton Review, and VarsityTutors (app). These are some great resources to study a particular topic or the whole course in general.
The answer is B
China was never nearly bankrupted because they had a very strong economy. During the silver trade, European countries shipped silver to east Asia and the Chinese soon required all of the merchants to pay in silver which made their products must easier to purchase.
5 = liquid water changing into water vapor
6= a puddle dries up after a rain shower
7= a pot of water on a stove reaches it's boiling point
8= clouds form from water vapor I. the sky
