The table shows that amphibole has a density 3.3 g/cm^3; feldspar has 2.6 g/cm^3, garnet has 4.2 g/cm^3, and finally quartz has 2.7. This means that garnet has the greatest density.
The diameter of the largest particle that would be carried at point A when the velocity of the Battenkill River is 50 cm/s is 0.8 to 1.1 cm.
So, The answer ranges from any value of 0.8 cm to 1.1 cm.