Looks like Enforcer cant possibly hit anyone. You can shoot at the woods though, hvy woods will turn into light if they take 40 damage and light to rough ground if they take 50(cumulative). Terrain has a -4 modifier(="immobile target") to hit.
EDIT:
Now that we are in the firing phase, some notes...
Lao Hu: has both cluster and standard ammo. Cluster gets a to-hit bonus but its damage is spread out and average damage is less than standard shell's.
Enforcer: UAC/10 can fire 1 or 2 shots. The 2-shot mode has 1/36 chance to jam the weapon, generates double the heat, spends 2 ammo (you have 20 shells). The second shell has a 42% chance to hit IF the first shell also hits - thus the dual shot or "ultra mode" is useful only when the to-hit chance is pretty high and/or you really want the target dead right now.
Argus: you have the Rotary autocannon. It can fire 1 to 6 shots. Any more than 1 shot and theres a chance to jam the weapon, but unlike UACs the RACs can be unjammed. You have 40 shells in total. Your to-hit chances are rather low now so you probably want to fire just 1 shot now and later increase the rate of fire to 3 for minimum chance to jam and to 5 when the to-hit chances are good. 6 is preferred only for emergencies.
EDIT 2: Uhh. Theres actually an error in the edited screenshot above. The distance between Lao Hu and Argus is actually 13 and not 14... Though it doesnt chance much. 14 is already medium range for Argus' LRMs so it actually CAN hit the Lao Hu, albeit at very low odds. My Jinggau is an easier target.