Answer:
This is a question of whether 91 is a prime number or not. And it is not so Mrs. Fisher is right, you can arrange them in 7 rows and 19 columns or vice versa. 7 and 13 are factors of 91.
45
Step-by-step explanation:
2/9 = 10/m
m = 10*9/2
m = 90/2
m = 45