Answer:
C) A ratio based on the mass of a carbon-12 atom
Explanation:
For each element, there is a characteristic number of protons, this number represent a type of atom and its called the atomic number
On the other hand we have the number of neutrons, and for one element which difers only on the number of neutrons, we have different isotopes from one element.
Together, protons and neutrons define the mass number
One property linked with the mass number, is the atomic mass, which is formerly expressed as "uma" (atomic mass unit)
By definition, one atom of carbon-12 (with 6 neutrons) has an atomic mass of 12 umas
Answer:
Ventricular systole
Explanation:
This contraction causes an increase in pressure inside the ventricles, being the highest during the entire cardiac cycle. The ejection of blood contained in them takes place. Therefore, blood is prevented from returning to the atria by increasing pressure, which closes the bicuspid and tricuspid valves.
C- Stratus clouds are the rainy clouds.
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Answer:
see below
Explanation:
alluminium is,
1.lustrous
2.highly malleable
3.reactive metal
4.some times acts as non metal
5.good conductor
6.obtained from bauxite
7.Atomic number 13 so electrons and protons are 13
8.neurons are 14
9.ductile
10.melting point is very high approximately 660 degree celsius.