The answer is; in the summer
Insects such as blowflies increase their population in the summers when the temperatures are warm. One reason is that most insects are ectotherms hence their body temperatures are dependent on ambient environmental temperatures. In addition, the maggot stage of the blowfly pupates mostly in warm and dry conditions hence increasing winged flies populations in the summer.
Under normal conditions it is not toxic
Adding ammonium nitrate to water turns the mixture cold and is a good example of an endothermic chemical reaction
You should use a Punnett Square for this question
The Punnett square predicts the offspring of two parents (two alleles). In this case you have brown eyes (Bb) and blue eyes (bb)
In the four boxes you should have Bb, Bb, bb and bb (50% chance of offspring with blue eyes and 50% chance of offspring with brown eyes).
The genotypes ratio will be 2Bb:2bb
And the phenotypic ratio will be 2 Brown : 2 Blue