Changes

The strategy sells 150 contracts - commission = $0.05 * 99 + $0.03 * 51 = $6.48

The strategy buys 3000 contracts - commission = $0.05 * 99 + $0.03 *900 + $0.01 * $2001 = $51.96</div>

::The strategy sells 150 contracts - commission = $0.05 * 39 + $0.03 * 111 = $5.28

::The strategy buys 3000 contracts - commission = $0.03 *789 + $0.01 * 2211 = $45.78

The strategy sells 150 contracts - commission = $1.25

The strategy buys 3000 contracts - commission = $1.5</div>

::The strategy sells 100 contracts - accumulated voume = 330 - commission = $0.75

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