Please help, even if you only know 1 answer.
1. The length of each side of rectangle R is an integer, and the area of R is 2009. What is the largest possible perimeter of R?
2. If i place all three operational symbols +, -, x, in all possible way into the blanks if the expression 5_4_6_3, only one symbol blank, each resulting expression will have a unique value. What is the largest of these values?
3. How many integers n > 0 satisfy 3/65 < 1/n < 9/100
Thanks