3) A certain type of cell doubles every 4 hours. If you started with 30 cells, how many would you have after 20 hours?

I think u would do 20/4. Which is five. Then 5*2=10. Add the ten to the thirty. Final answer is 40

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.