What is half of 7 minutes 24 seconds

Im gonna fail 7th grade selective breeding 1. creates offspring which are genetically identical to the parent 2. is the process of breeding only organisms with desirable traits 3. involves the removal of the nucleus of a cell 4. combines traits from organisms of different species

If a is a nonzero real number then the reciprocal of a is

What expression is equivalent to (84+16)