1. **Problem 1: Addition of Integers** The temperature starts at $-7^\circ C$ and changes by $+5^\circ C$, $-3^\circ C$, and $+8^\circ C$ over three hours. 2. **Formula:** To find the final temperature, add all changes to the initial temperature: $$\text{Final temperature} = \text{Initial temperature} + \text{Sum of changes}$$ 3. **Calculate the sum of changes:** $$5 + (-3) + 8 = 5 - 3 + 8 = 10$$ 4. **Add to initial temperature:** $$-7 + 10 = \cancel{-7 + 7} + 3 = 3$$ So, the final temperature is $3^\circ C$. 2. **Problem 2: Subtraction of Integers** The student started with a balance of $-250$ and ended with $180$. We want to find how much money was added. 3. **Formula:** $$\text{Money added} = \text{Final balance} - \text{Initial balance}$$ 4. **Calculate:** $$180 - (-250) = 180 + 250 = 430$$ So, the student added 430 to the account during the week.