The Comparative Condensed Income Statements of Marks Corporation Are Shown

The comparative condensed income statements of Marks Corporation are shown below. $\begin{array}{c} \text { MARKS CORPORATION }\\ \text { Comparative Condensed Income Statements }\\ \text { For the Years Ended December 31}\\\\\begin{array}{lcc}& 2017 & 2016 \\ \text { Net sales } & \$ 620,000 & \$ 500,000 \\ \text { Cost of goods sold } & 450,000 & 400,000 \\ \text { Gross profit } & 170,000 & 100,000 \\ \text { Operating expenses } & 54,000 & 40,000 \\\text { Net income } & \$ 116,000 & \$ 60,000 \\\end{array}\end{array}$ Instructions
(a) Prepare a horizontal analysis of the income statement data for Marks Corporation using 2016 as a base. (Show the amounts of increase or decrease.)
(b) Prepare a vertical analysis of the income statement data for Marks Corporation in columnar form for both years.