PT 61, Sec. 2, Q. 24. Ran into this problem yesterday and made a note to go back to it and try to find questions like it because the conditional logic is unconventional, at least to me.
If anyone wants to review PT68 with me tomorrow (Friday) over google hangout/skype. private message me and we can get started. Logical reasoning, both sections.
For example, PT 126 Section 3 Question 14 ... several PT's. For example, see PT 127, Section 2, Question ... answer. Additionally, see PT 127 Section 1 Question ... PT 19 Section 2 Question 18.