1.Scientists believed that chemical
The answer is definitely A. Houses. Basing on the Demographic Transition Model (DTM), countries categorized under stage 4 are said to have a stabilized population growth in other words birth and death rates are merely low. But still gradually on increasing number. As total population increases, housing now becomes insufficient. Examples of Stage 4 countries: Brazil, China, Argentina, Singapore, U.S.
Abraham founded Hebrew monotheism.
It is <u>true </u>that one of the principles of communication is that it is repeatable. You can communicate with other people as much as you want to, you can even talk about the same thing over and over again. This means that this type of communication can be repeated, which makes this sentence true.