We should save the document regularly when working on the document. If the app breaks down, you'll still have the file with your progress. To be extra safe, save the document in multiple places including the computer itself, also your USB drive. just so in case if the computer breaks down, you still have your USB drive.
Key is to lock as D. Substrate is to active site.
The "Rr" is heteroyzgous red
The "RR" is homozygous dominant
The "rr" is homozygous recissevie