An instrument is used to measure the height of an object above sea level. The height, in metres, is shown on the dial. [Figure: Dial showing heights from -80 to +80]

1. (a)What is the reading on the dial?[1]
2. (b)The object moves from position A, where the dial reads –54, to position B, where the dial reads + 48. What is the difference in height between A and B?[1]

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