crossover ?

Hi guys, was wondering what's the best crossover for a BIC America f12 40-180hz.
i'm not sure what this speaker name is but this is the settings of them Lower -3dB Limit: 125Hz Upper -3dB Limit: 20kHz ,95Hz-22kHz 8 Ohms 89 dB
what would be the best setting crs for this speaker i was thinking 140hz? i'ts a 7.1 system

Whats the rest of the speakers ? 140 off the bat sounds way too high but not knowing the rest of the speakers we can't comment.

Also, how the speakers are hooked up, if your using the crossover on the sub or the one in the receiver.

The Crossover will be on the sub,friend told me the name is tl1 white 7 of them and tl1 center.
i was wondering do they sell the tl center in white ?