Which statement best describes a situation in which opposite quantities combine to make 0?

In the middle of the afternoon, the temperature outside was 0 °F. An hour later, the temperature had decreased by 12 °F. An hour after that, the temperature had decreased by another 4 °F. What increase in temperature is needed to return to the original temperature of 0 °F?

Jaime hiked for 3 days across an island. He started at the shoreline, which is at an elevation of 0 feet. At the end of day 1, Jaime had gained 2,150 feet in elevation. At the end of day 2, he had gained an additional 1,970 feet in elevation. On day 3, Jaime hiked down to the shoreline on the other side of the island, which is also at an elevation of 0 feet. How many feet in elevation did he lose on day 3?

Kareem has a total of $123 saved. Which situations will result in Kareem having no money left in savings?