Scientists investigated factors affecting the rate of photosynthesis in tomato plants. The tomato plants were growing in a commercial greenhouse in the UK during winter.
Figure 5 shows the results.

Farmers growing tomatoes commercially try to control the rate of photosynthesis and
make maximum profit.
A farmer can control the temperature and carbon dioxide concentration in
a greenhouse.
- What is the minimum light intensity a farmer should use to get the maximum rate of
photosynthesis shown in Figure 5?
-The light intensity you gave in Question 05.3 may not give the farmer maximum profit.
Explain why.