<span>The answer is Due to heating of the air by the engine exhaust. Contrails are formed when the hot exhaust of the plane engines is rapidly cooled by the cold air in the upper atmosphere. The water vapor in the engine exhaust, formed in the combustion of fuel, freezes immediately to ice crystals due to the low pressure and -36oC temperatures in the 8000 m altitude in which the planes cruise. </span>
Answer:
as the blood pressure increases, the rate of blood flow decreases
Mitosis is the term i believe you're looking for
It is in standard notation
in scientific notation it would be is 5.4 x 10^6
Answer:
nuclear fusion
Explanation:
When the density and temperature at the core of the gravitationally collapsing nebula reaches values when nuclear fusion is triggered and sustained, that marks the birth of the star.