Here's how to calculate the concentration of silver in ppm (parts per million):

1. Convert tons to grams:

* 1 ton = 907,185 grams

2. Calculate the mass of silver in 1 gram of ore:

* (2.88 g Ag / 907,185 g ore) = 3.17 x 10^-6 g Ag/g ore

3. Convert to ppm:

* 1 ppm = 1 mg/kg = 1 µg/g

* (3.17 x 10^-6 g Ag/g ore) * (10^6 µg/g) = 3.17 ppm

Therefore, the concentration of silver in the ore is 3.17 ppm.