The majority of dog modeling agencies are in Hollywood, CA but here is some helpful info from an article written by a person who has dogs that are models:
Your best bet for finding a local agency is to talk to a local obedience school that offers modeling classes. They should be able to help you find a local agent.
Average atomic mass is closest to its most commonisotope.
You can find a dog's mass by wieghing it. Dogs usually have a different mass.
The two elements with the closest atomic mass are Bromine (atomic mass 79.9 amu) and Krypton (atomic mass 83.8 amu). They have a difference of only 3.9 atomic mass units.
Zirconium has the closest mass being 91.2g/mol
Venus at 81.5% the mass of Earth.
The element that has the closest mass to 89 is Yttrium(88.91).
Dubnium's mass number is about 262, because it is the atomic mass of the closest stable isotope.
Venus
Cape race
Framingham, MA.
The closest I can come is 782.2