A 150-kg object takes 1.5 minutes to travel a 2,500-meter straight path. It begins the trip traveling 120 meters per second and decelerates to a velocity of 20 meters per second.

What was its acceleration?

A. [tex]$-1.11 \, \text{m/s}^2$[/tex]
B. [tex]$-0.3 \, \text{m/s}^2$[/tex]
C. [tex]$+1.11 \, \text{m/s}^2$[/tex]
D. [tex]$+80 \, \text{m/s}^2$[/tex]

Let's solve this problem step-by-step to find the acceleration of the object.

1. Identify the Given Information:
- Initial velocity ([tex]$v_i$[/tex]) = 120 meters per second (m/s)
- Final velocity ([tex]$v_f$[/tex]) = 20 meters per second (m/s)
- Time taken for the journey = 1.5 minutes

2. Convert Time to Seconds:
We need to convert the time from minutes to seconds because velocities are given in meters per second.
[tex]\[
\text{Time in seconds} = 1.5 \text{ minutes} \times 60 \text{ seconds/minute} = 90 \text{ seconds}
\][/tex]

3. Calculate Acceleration:
Acceleration ([tex]$a$[/tex]) can be determined using the formula:
[tex]\[
a = \frac{v_f - v_i}{t}
\][/tex]
Plugging in the values:
[tex]\[
a = \frac{20 \, \text{m/s} - 120 \, \text{m/s}}{90 \, \text{s}}
\][/tex]
[tex]\[
a = \frac{-100 \, \text{m/s}}{90 \, \text{s}} \approx -1.11 \, \text{m/s}^2
\][/tex]

4. Choose the Correct Answer:
The calculated acceleration is approximately [tex]$-1.11 \, \text{m/s}^2$[/tex].

Thus, the acceleration of the object is [tex]$-1.11 \, \text{m/s}^2$[/tex], which corresponds to the first option.