How do you write 7,870 in scientific notations ?

Yolanda wanted to buy a total of 6 pounds of mixed nuts and dried fruit for a party she paid 21.60 for mixed nuts and 11.90 for dried fruit did yolanda but enough mixed nuts and dried fruit for the party

Which expression equals 9^3 sqrt 10 a. 5 sqrt 10 + 4 sqrt 10 b. 5^3 sqrt 10 + 4 ^3 sqrt 10 c. 5 sqrt 10 + 4^3 sqrt 10 d. 5^3 sqrt 10 + 4 sqrt 10

Amovie theater owner determined that about 2 out of every 5 customers purchases popcorn. which simulation could be used to answer questions about customers purchasing popcorn?