Answer:
A. chemical substance whose atoms all have the same number of protons
Explanation:
An element is a substance which contains identical atoms that have the same number of protons in the nucleus.
Elements are arranged in the periodic table according to their atomic number (= number of protons): so atoms of different elements have a different number of protons in their nuclei.
For a neutral atom, the number of electrons around the nucleus is also equal to the number of protons.
Moreover, atoms of the same element can have a different number of neutrons, despite having the same number of protons - these atoms are called isotopes.
the outermost layer of Earth’s lithosphere that
is found under the oceans and
molded at scattering
centres ono
ceanic ridges, which occur at deviating plate boundaries
Oceanic crust is about 6 km (4 miles) thick.
hope it helps
Answer:
upwards
downwards
Explanation:
Given:
weight of the person, 
So, the mass of the person:
- Now if the apparent weight in the elevator,
<u>Then the difference between the two weights is :</u>
is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:
upwards, because the normal reaction that due to the weight of the body is increased here.
- Now if the apparent weight in the elevator,
<u>Then the difference between the two weights is :</u>
is the force that acts on the body which generates the acceleration.
Now the corresponding acceleration:
downwards, because the normal reaction that due to the weight of the body is decreased here.
By studying meteorites which are the most ancient material in space.
