sand explorers corp. incurred cost of 17.1 million for the rights to extract resources from a natural gas deposit. sand explorers expects to extract 9.0 million cubic feet of natural gas during a six-year period. natural gas extracted during years 1 and 2 were 88000 and 16200000 cubic feet, respectively. what was the total depletion for year 1 and year 2, assume the company uses the units-of-production methdo?