Question

a student is graphing the effect of fertilizer on plant height. which variable belongs on the x-axis?
plant height (cm)
type of plant
amount of fertilizer (grams)
temperature of the room

a researcher is investigating how the amount of carbon dioxide in the air affects the rate of photosynthesis in a certain type of plant. he uses ten identical plants and places them in ten closed environments that are identical except for the amount of carbon dioxide in the air. he measures the amount of oxygen each plant produces to determine and compare their photosynthetic activity. what would be the best data display for comparing the photosynthetic activity of the 10 plants?
a labeled sketch
a pie chart
a bar graph
a line graph

Explanation:

First Question:

In an experiment graphing the effect of fertilizer on plant height, the independent variable (the one manipulated) is placed on the X - axis. The amount of fertilizer is the independent variable here as it's what's being changed to see its effect on plant height. Plant height is the dependent variable (on Y - axis), type of plant and room temperature are not the main variable being tested here.

A bar graph is used to compare different groups or individuals. Here we have 10 plants (different individuals) and we want to compare their photosynthetic activity (measured by oxygen production). A labeled sketch is for illustration, a pie chart is for showing proportions of a whole, and a line graph is for showing trends over time or continuous data. Since we are comparing 10 discrete plants, a bar graph is best.

Answer:

C. Amount of fertilizer (grams)

Second Question: