How long in minutes would it take to fabricate a 4 colored ball 6cm in diameter using FDM? Assume a layer thickness of 0.5mm , a width of 0.9mm , and the extrudate being deposited at a rate of 3cm/sec. The stage movement time is 0.5sec per layer, and it takes 8secs to switch between any two materials. Assume the support structure has a volumetric fill ratio of 100%.