You must prove using the method specified. You must write clearly and in complete sentences. Make sure you read the hidden quantifiers in the sentences so that you can interpret the structure of the sentences correctly.

(2) The domain is integers.

(2a) (4 pts) Write the following using logical connectives, quantifiers, and required mathematical symbols: If the sum of the squares of two integers is not a multiple of 4 then at least one of the integers is odd.

(2b) (8 pts) Prove the proposition in (2a) by contraposition.