Consider columns A and B of the sample table above. You now want to vary not just the quantity produced annually, but also the selling price, and you are interested in the profit in each case.
观察上面示例工作表中的列 A 和列 B 。您现在不但要把年产量的数量作为变量，而且要把出售价格也作为变量并且考虑利润。