Consider the following premises. If Mary plays squash, then Michael is writing a letter. Jennifer is a politician if and only if Richard is making tea. If Michael writes a letter, then Richard is making tea. Can we infer the following from them? The fact that Mary plays squash does not imply that Jennifer is a politician.
 From the fact that Jennifer is a politician if and only if Richard is making tea we can infer that if Richard makes tea, then Jennifer is a politician. From the fact that if Michael writes a letter, then Richard is making tea, and that if Richard makes tea, then Jennifer is a politician we can infer that if Michael writes a letter, then Jennifer is a politician. Finally, from the fact that if Mary plays squash, then Michael is writing a letter, and that if Michael writes a letter, then Jennifer is a politician we can infer that if Mary plays squash, then Jennifer is a politician, which contradicts that The fact that Mary plays squash does not imply that Jennifer is a politician. Therefore, the answer is no.