Read the following and answer the questions that follow.
Divya draws a pencil line near one end of a strip of chromatography paper and places a small spot of black ink at its centre. The paper is suspended in a beaker containing water such that the ink spot remains above the water level. As the water rises through the paper, the black ink separates into blue, green, and yellow spots.
Paper chromatography
1. Which of the following observations confirms that separation has occurred during paper chromatography?
2. Why is a pencil used to draw the baseline instead of a sketch pen?