The input nums is supposed to be an array of unique integers ranging from 1 to nums. Length (inclusive). However, there is a mistake: one of the numbers in the array is duplicated, which means another number is missing. Find and return the sum of the duplicated number and the missing number.

In the image, layer a is the topmost layer. layer c contains fossils from the precambrian era. layer b contains dinosaur fossils, and layer a contains fossils of mammals. which two statements are supported by this evidence? 1. mammals lived before the precambrian era. 2. dinosaurs and mammals existed in the precambrian era. 3. dinosaurs evolved after precambrian organisms. 4. precambrian organisms evolved after dinosaurs. 5. precambrian organisms were the first life-forms to become fossilized, according to this sample.