It depends on how the accident happened.

If the commercial vehicle hit a private passenger auto because the private passenger auto pulled out into the path of the commercial vehicle….then the driver of the private passenger auto is the cause of the accident. The commercial auto insurance carrier would not pay them anything.

So, you can file a claim. But it does not mean you will get paid. If you get paid, depends on how the accident happened.

Of course you can. You will probably end up suing. Consult a lawyer

Yes, you will get paid compensation by the negligible driver’s insurer.

Oh yes. Big time.

that is part of pain and suffering. Death is big time suffering.
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Here are the partial list of items that can go under pain and suffering

(1) broken bone
(2) loss of life
(3) loss of limb
(4) loss of use of bodily function
(5) loss of time from work

there’s more.

Good Luck…