Answer:
0.54 lillies per square meter.
Explanation:
First we calculate the area:
Area = length * width
Area = 6 m * 4 m = 24 m²
The we divide the population of lillies (13) by the area, to calculate the population density:
13 lillies / 24 m² = 0.54 lillies/m²
So the population density is 0.54 lillies per square meter.