Approach checklist question 737-800
From the checklist:
"Position landing gear lever down, flap lever to the 15 detent. Position engine start switches to CONT. Check RECALL"
What does detent mean?
What would "Check RECALL" be referring to in the above instance?
GPWS "PLUS HUNDRED"
What is the GPWS plus hundred check referring to in the approach to landing?
Thanks