TP, Ill answer those questions that I can,
1, The 'trailing lines' are static wicks which allow the static charge which builds up on an aeroplane as it flies to dissipate. This reduces its chances of being struck by lightning.
2, The cable between the aileron and the wing is a bonding wire which ensures all parts of the airframe are at the same electrical potential. Also provides a path for a lightning strike to avoid it travelling through the control cables with catestrophic damage.
3, I dont remember seeing pitot and static drains on a 152 - Ask your instructor.
4, LL = low lead
5, Different aerials will be VHF COM, VOR ADF, DME, XPDR again ask your instructor.
6, No
7, A safety briefing should include information as to how to adjust seat and how to don, doff and adjust seatbelt, How to open doors and the location and use of emergency equipment (axe, fire extinguisher etc) What to do in the event of a forced landing (remove specs Brace etc) and any other questions that the passenger/examiner may have.
Good Luck!