Fact 1: Staying warm has a positive impact on an animal 's survival. Fact 2: With a thick fur coat and 4 inches of fat a bear stays warm. Given the two facts above, what has a positive impact on an animal's survival?
Pick from: 1. four limbs; 2. sensory neurons; 3. low water availability; 4. fur and fat; 5. loss of food; 6. heat energy; 7. hormones; 8. destruction of habitat;
4.