Answer: Option #4: the 0.2 could be changed to 2.
Explanation:
The table is designed to make the concept of percentages more understandable. The table first allocates the total amount of 70 in terms of its "fifths," or 20% parts. Then it expresses these parts in the last row of the table, showing that 20% of 70 is 14 and all the five parts sum up to 70 again.
Now, Mikel is supposed to express 40% of the amount. So she writes (incorrectly): 0.2 * 14. This statement needs to be changed to 2 * 14 (two times 14 = 28), to correspond to 2 times 20%, or 40% of 70.
This is reflected in the last (fourth) option "The 0.2 in the expression could be changed to 2."
Option #3 is incorrect because changing 14 to 70, will result in an incorrect number (2.8).
Options 1 and 2 are similarly incorrect (as can be easily verified)