What you will do when you line manager asks you to do tasks that are not in your duties and you will not get paid for it?

I would do insure that I get the task done because it will form a part of new learn which will improve my growth and expose me to a new skill. However I will insure that I let my boss that this is not a apart of my job and if it will be a repeated task then I would expect an increment should I master the skill and in the interim I will not take responsibility for any errors that may arises as I do not know how to do it

Evaluate.

After identifying talent, most good managers attempt to build upon it by assessing how well extra tasks are carried out. Some even prefer to train you by getting you to do a task you may consider beyond or below your duties. The said task may be beneath or above your 'pay grade' but that doesn't mean it is beyond your capabilities.

On the other hand, some tasks require specific and specialized training. To take upon a task that you are not trained to handle may cost physical or fiscal harm, not to mention loss of trust within your team. Hence my first answer; evaluate. The question should not be "is this my duty?" or "am I getting paid for this?", but "am I trained and equipped to handle this?" or "is this a test?" and "am I recieving hands on training?"

He is my manager and his rightAccording to the mission and within the limits of my specialization