Being asked to perform a job that is out of job description...?

Helping out this team will put you on the fast track to that tech position should this current co-worker turn out to be the wrong fit for the job. You will also make a good impression with the boss. You can always "hold my ground" of course, but that will likely get you fired. Good luck.

It's up to you how you want to deal with it. You can offer your ideas and then go back to shipping/receiving or you can tell them that if they wanted your ideas, they should have hired you for the tech position. I'm not going to tell you what to do.

More than likely, if your job HAS a formal job description, the last item reads something like "and other duties as assigned". You should also note that to the extent it doesn't interfere with performing your primary duties, assisting in other areas where you can is often a good way to increase your chances of getting a different position in the future.

It is less clear if not assisting would be grounds to fire you 'for cause', but if your boss decides you don't fit the company culture, that alone can be sufficient reason to terminate your employment.

Your an idiot. This isn't them asking you to do something their not paying you for. There testing you. Either their not happy with the new guy, or they need a another person.

If you do good, they give you a promotion and a raise. I would bet on it.

You can help, or you can look like a jerk and end up with them never wanting to promote you because you aren't a team player, and maybe fire you.

Will your decision help or hurt you? Definitely. They will not promote someone that isn't a team player.

If you give your best effort, you can prove them wrong. If you refuse, you prove they were right. Your call.

If you have a contract for a specific period that sets out your duties and has no reference to other duties that can be assigned, then you can enforce that contract for that period of time.

Go along with it... or quit.

For now, nothing has happened. THere is no reason to cause a stir.

If they come to you and ask you to do the work of the other job though, you have good grounds to tell them that if they wanted you to do it they should have given you the job. And if they fire you, you can sue them for wrongful dismissal.