The average age of a breed of dog is 19.5 years. If the distribution of their ages is normal and 20% of dogs are older than 22.6 years, find the standard deviation.

Panthers and leopards prey on deer in an ecosystem. for unknown reasons, the population of leopards increased drastically. what are the likely effects of this change on the species? 1. more food for panthers and more competition for leopards 2. less food and more competition for panthers 3. fewer deer and more competition for panthers 4. more food for deer and less competition for panthers and leopards 5. more food for leopards and less competition for panthers