Hi thanks for the reply.
the rotation will be limited to a max of 300 degrees, so I do think the single turn should be the best. My understanding is that if it's a 2turn pot, that means the resistance of the pot will vary from 0 to max when you turn it 2x encirclements.
As for temperature it will be in room temperature, so between 10 degrees to 30 degrees celcius. but what does it mean, or what is the application of ppm/C ?
lastly for the resistance value, we are measuring the output voltage. So we have a battery as the power source, we insert the pot and measure the output voltage