Answer:
their sum: 2.8m
their difference: 1.2m
the third side's length should be smaller than their sum, larger than their difference
it could be: 1.3-1.4-1.5-1.6-1.7-1.8-1.9-2-2.1-2.2-2.3-2.4-2.5-2.6-2.7 but since it has to be a whole number, 2m is the only eligible answer.
