Fiber and SFP Questions - What type of Fiber is this? (Pics included)

Hey guys,

Our company has recently purchased a facility off another company, but apparently as a part of the deal they get the networking switchgear back. Our current standard is Cisco SG200 and SG500 stuff at most of our sites (extremely simplistic networking).

I've been out of the networking game for over 10 years so I need some assistance regarding what type of SFPs I might need. My apologies if this is too simplistic of a question.

The site essentially has two trailers connected with underground fiber. See the second picture in this link -- this is LC fiber - correct?

Second question -- in the first picture from the link above, I'm at a bit of a loss. Why would a normal Cat5e cable be going into the slot here? On the other end it's just plugged in to one of the normal switchports... Maybe it's a 10/100 switch, and the module is Gig? That's the only reason I can think of why a module would be used there...