What are strata (give geologic time scale webquest answer)

Strata are layers of rock, or sometimes soil. In nature, strata come in many layers. It is a term in sedimentary and historical geology; the singular is stratum. ... The strata are often typical of a particular time and place, and allow geologists to relate rocks in different places.

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.