Chaparral Sand and Gravel purchased a pit for $900,000 that is expected to yield 6000 tons of gravel and 7000 tons of sand per year. If the gravel will sell for $6 per ton and the sand for $9 per ton,...

Chaparral Sand and Gravel purchased a pit for $900,000 that is expected to yield 6000 tons of gravel and 7000 tons of sand per year. If the gravel will sell for $6 per ton and the sand for $9 per ton, determine the annual depletion charge according to the percentage depletion method.