Use logarithmic (audio) pots for volume, and use linear pots for tone.
Since it's a jazz bass (and presumably has single-coil pickups), you'll probably want a resistance of 250K for all of the pots...if you go for 500K, the highs might be a little on the harsh side. However, if your pickups are stacked humbuckers or split-coil
Js, you might want to go with 500K.