Learners assembled the apparatus to determine how much water a leafy shoot takes up. At the beginning, they noted the position of the air bubble. They left the apparatus for $10$ minutes, recording the distance the air bubble moved at one-minute intervals. After that, they turned on a fan directed at the leafy shoot and, for a further $10$ minutes, recorded the distance the air bubble moved from the start at each minute. Which graph should they plot using their results?
Biology 5090 · O Level · Transpiration and translocation