Using Squelch & Using Mode Saved in Bookmarks

[BT-Justice]

How do you set the squelch exactly? I assume it is the -q option, but how do you set a negative value? I like to run the scanner at -60.0 dB. I tried this but it gives me the "Error: -q: option requires an argument":

-q -60.0

Now if I use this, the scanner works, but on activity it resets the squelch to -110.0 dB:

-q 60.0

Also, how do you tell the scanner to use the mode saved to the bookmark? I have a mix of AM and NFM frequencies I scan. The mode doesn't switch on activity.