(! my guess is either a or d but i want to make sure.)
is the following definition of dog reversible? if yes, write it as a true biconditional.
a dog is a mammal.
a. the reverse is false.
b. the reverse is true. an animal is a dog if (and only if) it is a mammal.
c. the reverse is true. an animal is a mammal if (and only if) it is a dog.
d. the reverse is true. if an animal is a dog, then it is a mammal.

You coordinate volunteers for litter cleanup in local parks. your spreadsheet lists drivers and the number of seat belts in each driver’s car. the spreadsheet calculates the number of drivers (d) and the total number of seat belts (s). you want to know the maximum number of volunteers, besides drivers, that can be transported to the park in a single trip given that each person must have a seat belt of their own.