Convection currents in the mantle are what causes the movement of tectonic plates. As the extremely hot molten material from the mantle rises toward the crust, it cools enough to become denser and sink back into the hotter area of the mantle.
Answer:
The displacement reactions are regarded as redox reactions because they involve the formal transfer of electrons from one chemical specie to the other
2) The series of reactivity of the metals in the order of increasing reactivity are;
↓
↓
Explanation:
1) Redox (oxidation-reduction) reaction is a chemical reaction involving the loss and gain of electrons from one chemical species to another, where the chemical species that undergoes oxidation, loses electrons and is termed the reducing agent, while the other chemical species that undergoes reduction, gains electrons, and is termed the oxidizing agent
2) The redox reaction can being based on the affinity for electrons depends on the positions of the reactants in the electrochemical series as well as the chemical reactivity of the metals with zinc being a stronger reducing agent and more chemically reactive than copper and magnesium being a stronger reducing agent and more chemically reactive than zinc
Least reactive (Cu) < (Zn) < Mg Most reactive
Copper < Zinc < Magnesium.
Answer:
Air
Explanation:
It takes up space/ the rest do not
Answer:
The pressure in mmHg is 1253 (option C)
Explanation:
Two quantities are directly proportional if when multiplying or dividing one of them by a number, the other is multiplied or divided by that number. In other words, the magnitudes are directly proportional when one magnitude increases and so does the other in the same proportion; or when one magnitude decreases and so does the other in the same proportion.
The rule of three or is a way of solving proportionality problems between three known values and an unknown value, which can be applied to directly proportional quantities as follows:
a ⇒ b
c ⇒ x
So 
where a, b and c are data and x is the unknown value to be calculated.
In this case, knowing that 1 Torr = 1 mmHg, the rule of three can be applied as follows: if 1 torr is equal to 1 mmHg, 1253 torr is equal to how many mmHg?

pressure= 1253 mmHg
<u><em>The pressure in mmHg is 1253 (option C)</em></u>
A is correct. water is incompressible, so it will always have the same density, regardless of volume