Question

1. a weather station recorded the temperature changes in a city over five consecutive days. the initial temperature on day 1 was 10°. the recorded changes in temperature at the end of each day are shown in the table. which statement is true? a. the temperature decreased by 3° on day 2, resulting in 7° at the end of that day. b. the temperature decreased on day 3. c. the temperature did not increase or decrease on day 4. d. the temperature is 1/2 at the end of day 5. day change in temperature day 1 +2 day 2 -3 day 3 3 day 4 0 day 5 -2

Explanation:

Step1: Analyze Option A

Initial temp on Day 1 is $10^{\circ}$. Change on Day 2 is $- 3^{\circ}$. So temp at end of Day 2 is $10+( - 3)=7^{\circ}$. But we don't know if this is the overall temp decrease on Day 2 compared to start of Day 2 (since we don't know start - of - Day 2 temp relative to start of Day 1 in terms of decrease from start of Day 1), so we need to calculate overall.

Step2: Calculate overall temps

Starting temp on Day 1 is $10^{\circ}$.
Temp at end of Day 1: $10 + 2=12^{\circ}$ (because change on Day 1 is $+2^{\circ}$).
Temp at end of Day 2: $12+( - 3)=9^{\circ}$. So option A is wrong.

Step3: Analyze Option B

Change on Day 3 is $3^{\circ}$, which means the temperature increased on Day 3, not decreased. So option B is wrong.

Step4: Analyze Option C

Change on Day 4 is $0^{\circ}$, which means the temperature did not increase or decrease on Day 4. This option is correct.

Step5: Analyze Option D

Temp at end of Day 4 is the same as at start of Day 4 (since change is $0^{\circ}$).
Temp at end of Day 4: Let's calculate from start. Temp at end of Day 1 is $10 + 2=12^{\circ}$, at end of Day 2 is $12+( - 3)=9^{\circ}$, at end of Day 3 is $9 + 3=12^{\circ}$, at end of Day 4 is $12+0 = 12^{\circ}$, at end of Day 5 is $12+( - 2)=10^{\circ}$, not $\frac{1}{2}^{\circ}$. So option D is wrong.

Answer:

C. The temperature did not increase or decrease on Day 4.