Required: 1. Calcuiste the number or heimers heao-Frst must seiv to eam operating income of 881,000 . 2. Check your answer oy preparing a contitbusion margin income statement ossed on the number of units calcuisted. Amount Descriptions Refer to the ist beiow for the exact wording of text ltems whin your income statement. Amount Descriptions Operating income Operating loes Saies Total contributian margin Total fixesd cost Tobal variable cast Number of Helmets 1. Caculate the number or hemets Haad-First must sev to eam operaing income of 581,000