What is meant when departure control instructs you to “resume own navigation” after you have been vectored to a Victor airway?

(Refer to figure 87.) Which VHF frequencies, other than 121.5, can be used to receive De Ridder FSS in the Lake Charles area?

On the runup pad, you receive the following clearance from ground control:

CLEARED TO DALLAS LOVE AIRPORT AS FILED — MAINTAIN SIX THOUSAND — SQUAWK ZERO SEVEN ZERO FOUR JUST BEFORE DEPARTURE — DEPARTURE CONTROL WILL BE ONE TWO FOUR POINT NINER. An abbreviated clearance, such as this, will always contain the

How is your flight plan closed when your destination airport has IFR conditions and there is no control tower or flight service station (FSS) on the field?

When operating under IFR with a VFR-On-Top clearance, what altitude should be maintained?