According to a recent encyclopedia entry about dog breeds, labrador retrievers come in two specific breeds: english and american. the article cites six studies from several scientific journals about dog breeding showing that males of both breeds usually average 29-41 kg (65-90 lb) in weight, and females usually average 25-32 kg (55-70 lb) in weight. anna’s female labrador retriever weighs 38 kg (83 lb). what does anna’s dog’s weight indicate about the reliability of this source?