Does anyone know what's wrong with this code

Assume that there is a 4% rate of disk drive failure in a year. a. if all your computer data is stored on a hard disk drive with a copy stored on a second hard disk drive, what is the probability that during a year, you can avoid catastrophe with at least one working drive? b. if copies of all your computer data are stored on three independent hard disk drives, what is the probability that during a year, you can avoid catastrophe with at least one working drive?

So im doing this school challenge and the teachers said whats the average text a student gets a day so i need to get about 20 in a day but dont know how can you guys 2163371293

All of these are true about using adhesive except: a. dissimilar materials can be joined. b. mixing tips are product and material specific. c. a specific application gun may be required. d. two-part adhesives are dispensed using two mixing tips