A graph titled "Average plant height (cm) vs. Concentration of sodium phosphate (mg/L)" shows an upward-sloping line that reaches a maximum
value and then stays there over the remainder of the graph.
Average plant height (cm) vs.
Concentration of sodium phosphate (mg/L)
50
40
Average plant height (cm)
30
8
10
Concentration of sodium
phosphate (mg/L)
What noticeable trend from this graph might be used to make a conclusion?