What do historians study when attempting to make connections between ancient civilizations and world cultures of today? A.
birth rates

B.
nuclear families

C.
death rates

D.
cultural hearths

D. Cultural hearths

Explanation:

When attempting to make connections between ancient civilizations and world cultures of today, historians and other scientists who study human history and culture (such as anthropologists and archeologists) study cultural hearths. A cultural hearth is an area where a civilization first began.  Some examples of ancient cultural hearths are Mesopotamia, the Nile River Valley, and the Wei-Huang River Valley. These civilizations were incredibly influential, and we need knowledge about them in order to better understand the cultures of today.

because the two particles have an equal charge, the charges will cancel out and give the atom an overall charge of 0. so, if at atom has 35 protons in the nucleus, we could expect it to have 35 electrons orbiting that nucleus.