What is community property and associative property

It's "commutative property," which says that (for addition/multiplication) order of the operator doesn't matter. For eg, 3 * 5 = 5 * 3.

Associative property (again, of multiplication and addition) means that it doesn't matter how you solve an expression if the same operand is used and some numbers are grouped. For eg. 3 * (5 * 4) = (3 * 5) * 4.