Final answer:
Adam knows that if 4 + 7 = II, then 7 + 4 = II as well, due to the commutative property of addition.
Step-by-step explanation:
Adam knows the commutative property of addition, which states that the order of numbers doesn't affect the sum. This means that if Adam knows 4 + 7 = II, he also knows that 7 + 4 = II. The commutative property allows us to rearrange the numbers without changing the result. Adam knows this new fact because he understands the commutative property of addition.