Can you me with this l will give you brainliest.

What is the fewest number of full weeks briyana would have to work to have enough money? 8 weeks9 weeks 10 weeks11 weeks

Aword processing program requires a 7- digit registration code made up of the digits 1,2,4,5,6,7 and 9 each number has to be used and no number can be used mor than once how many codes are possible

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.