The student performed an experiment to test his hypothesis about sunlight and plant height using two plants. he kept everything the same between two tomato plants except he exposed them to different amounts of sunlight. he also used a third plant as a control group, or a group in which no variables are manipulated to confirm the results. roberto critiqued the work. which problem did roberto most likely identify?

a.) the sample size is too small.
b.) too many variables are manipulated.
c.) it is not possible to keep the conditions the same.
d.) controls should only be used in studies of animals.

The correct answer would be A.) The sample size is too small.

Sample size refers to the total number of observations or participants taken into consideration while performing an experiment or in a study.

It is suggested that the sample size should be kept as high as possible.

It helps in increasing the reliability, precision, and reproducibility of an experiment.

As the student used only two plants for the experiment so, we can not be sure if the results were scientific or just a matter of chance.

imagine a line passing through the center of earth that goes through both the north pole and the south pole. this imaginary line is called an axis. earth spins around its axis, just as a top spins around its spindle. this spinning movement is called earth's rotation. at the same time that the earth spins on its axis, it also orbits, or revolves around the sun. this movement is called revolution.