I believe it is E. Could be wrong though.<span />
Molecular biologists are interested in things like the level of gene expression (how much protein or RNA is present at any given time), which molecules are directly touching each other inside the cell, etc. ... Cell biology techniques, on the other hand, want to know what's going on inside intact cells.
( Try to see which one sounds best after reading this)
Its more natural and doesn't have side effects
Answer:
having more air spaces around the spongy mesophyll cells
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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