some bidding situations

For all hands, IMPs vs. the usual set of villains (our friends who
play a Precision system).

hand #1:

1st seat not vul vs vul

AQ8 97654 4 9873

P-1D!-1S-2C!-2S; P-P-3D-?

1D: could be short (includes 13-16 balanced)
2C: NFB

hand #2: not vul vs vul

AT KQT76 864 AJ5
K863 43 A5 KQ963

E-W pass throughout (W deals).  Do you you open the North hand 1H
or an 11-14 NT?  If a 1H opening is imposed, how do you think the
rest of the auction should go?

hand #3:

3rd seat not vul vs vul

void QJ9 AQJT85 AQ76

P-P-1D; 1S-P-P-?

How to balance here?  If you double, it continues

P-P-1D; 1S-P-P-X; P-2H-2S-?

now what?

hand #4: vul vs not

AKQ2 64 T93 KQJ6
765 AQJ9 765 AT8

East deals and opens 1D (could be short).  Opps are silent thereafter.
Suggest an auction.