问题如下：
The Fulcrum Company produces decorative swivel platforms for home televisions. If Fulcrum produces 40 million units, it estimates that it can sell them for $100 each. Variable production costs are $65 per unit and fixed production costs are $1.05 billion. Which of the following statements is most accurate? Holding all else constant, the Fulcrum Company would:
选项：
A. generate positive operating income if unit sales were 25 million.
B. have less operating leverage if fixed production costs were 10 percent greater than $1.05 billion.
C. generate 20 percent more operating income if unit sales were 5 percent greater than 40 million.
解释：
C is correct.
Because DOL is 4, if unit sales increase by 5 percent, Fulcrum’s operating earnings are expected to increase by 4 × 5% = 20%. The calculation for DOL is:
看了之前的讲解，是不是单凭现有条件，无法直接计算operating income?如果能计算，可不可以写一下公式？？
