Answer:
C. experimental
Explanation:
Experimental variables are the variables that are changed during the experiments to observe the effects of these changes. An experiment usually has one or more experimental variables. An experimental variable that is changed to know its impact on some other variable is called the independent variable.
In the given experiment, goldfishes were exposed to various temperature conditions to observe the effect of temperature on respiration. Therefore, both temperature and respiration rate are the experimental variables here.
An exponential growth graph looks pretty much like the right side of a parabola. The graph equation is f(x)= C ·a^x, so you can also plug in x values to find the y value. It's not a linear line, but it curves upwards starting from (0,0).
<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>