TIESULUI
Carboniferous
Jurassic
Thassic
Permian
Pennsylvanian
Mississippian
Devonian
Silurian
Ordoviciantes
Cambran
Precambrian
Paleozoic
Which method is most likely used to identify what happened before the start of the Paleozoic era?
O
Scientists study fossils from the Jurassic period.
Scientists observe index fossil records of the Mesozoic era.
Scientists examine fossil evidence during the Precambrian time
Scientists explore the emergence of mammals and humans in the Cenozoic era.

sorry i was late, but i don't know what assignment your talking about, i'm in flvs as well, im in earth space science. but u are behind pace bc every class should be in the 3's or 4'

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

56 moles of   lieter in chemistry

the cold front replaces the warmer air at the ground level changing the wind to be breezy and denser.there is also an immediate drop in the temperature.