Is it possible to determine the life span of the grasshopper or the mosquito?

Yes, a grasshopper's life cycle consists of three stages (Egg- Nymph- Adult) and one life cycle is completed in about 12 months which means that a grasshopper lives for about one year on an average.

A mosquito on the other hand has four stages in its life span (Egg, Larva, Pupa and Adult). A female adult mosquito is expected to live for 3-100 days. A male however, live for only about 10-20 days.