Mario performed an experiment to determine if photosynthesis was affected by the amount of light that a plant received. The data from his experiment are shown in the table below. Amount of light (hours) Number of plants Average volume of oxygen produced (mL) 1 4 0.50 6 4 2.0 10 4 5.0 What could he have done to increase the validity of his data? Reduce the number of plants. Remove the 1 hour group. Add a 0 hours control. Measure the oxygen in liters.

Add a 0 hour control

Explanation:

In an experiments, a control is what serves as a guide to measure the amount of change.

An experiment is made up of independent and dependent variable

the dependent variable is the variable to be measured that is varied and in this case its the number of light while the independent variable stands alone and been depended on by dependent variable. For more precision, the varied variable should have an experimental control that will serve as a check to know if indeed the varied number of light is of significance or not. If the control is having higher average performance than the experimental variable then it shows the control is more preferably but when the performance of the variable is higher than the control then its indicates that either one or some of the variable or all are equally better than the control and can be used.

your answer is true

i am 100% sure

explanation:

hydrogen is a compound or a single element and a element is a pure substence that cannot be separated into simpler subtances

clorine is a compound its a chemical substance that forms when two or more different elements combine

so both hydrogen and clorine are compounds