The answer is <span>Time is the independent variable, and the number of birds is the dependent variable. </span>
<span>An independent variable is variable that is not affected in the experiment. It is what experimenter controls. On the other side, a dependent variable is called dependent because it depends on the independent variables. It is what is affected during the experiment.
In Sam investigation, he controls time - he counts birds at 6 a.m. and 6 p.m. So, time is the independent variable. The number of birds is affected during the experiment, so it must be the dependent variable.
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There are many factors that affect the rate of chemical reactions and temperature is one of them.
Typically, the higher the temperature of a chemical reaction the faster the reaction occur, that is, the temperature and the rate of chemical reaction are directly related. This is due to the fact that increasing the temperature of the reaction increases the kinetic energy of the reacting particles and thus they are able to move faster and the reaction also occur faster. Thus, from the options given, the correct answer will be D [40 degree], this is because, it is the highest temperature out of all the options given.
The direction of the prevailing winds vary with latitudes.
The assisted transport of a molecule through the cell membrane in deprived of expenditure of energy is facilitated transport. It transports molecules via specific trans membrane integral proteins because of being passive the facilitated transport does not directly require chemical energy from ATP hydrolysis in the conveyance step itself but rather molecules and ions move down their concentration gradient.