c) The calculation that NASA scientists did to find the rate of increase in the change in global surface area temperature is best represented by: \( (0.9-0.1) \div(2020-1880) \) \( (0.9+0.1) \div(1880-2020) \) \( (-0.1+0.9) \div(2020-1880) \) \( (0.9-(-0.1)) \div(2020-1880) \)

The fourth option, \( (0.9-(-0.1)) \div(2020-1880) \), is the best representation for calculating the rate of increase in global surface area temperature. This equation effectively captures the increase from a low of -0.1°C (indicative of cooler temperatures) to a high of 0.9°C over the time span from 1880 to 2020, showcasing the overall warming trend. In practice, NASA uses this type of calculation to communicate the urgency of climate change to the public and policymakers. By breaking down complex temperature data into understandable statistics, scientists can highlight the need for immediate climate action and the importance of sustainability efforts, making the information more relatable to everyone.