Final answer:
The equivalent expression to 2.2Tt + 3.5 + 9.8 using the commutative property is 98 + 35 - 22 since the commutative property allows re-arrangement of terms.
Step-by-step explanation:
The commutative property of addition states that changing the order of the numbers being added does not change the sum. That is, A + B = B + A. Thus, the expression 2.2Tt + 3.5 + 9.8 can be re-arranged in any order without changing the value of the expression. Looking at the expressions provided, 98 + 35 - 22 is the equivalent expression when using the commutative property since it represents the same numbers re-arranged.