Ella completed the following work to test the equivalence of two expressions. 2 f 2. 6. 2 (0) 2. 6. 0 2. 6. 2. 6. 3 f 2. 6. 3 (0) 2. 6. 0 2. 6. 2. 6. Which is true about the expressions? The expressions are equivalent because Ella got different results when she substituted zero for f. The expressions are equivalent because Ella got the same result when she substituted zero for f. The expressions are not equivalent because Ella would get different results when substituting different numbers for f. The expressions are not equivalent because Ella would get the same results when substituting different numbers for f.