The result is -15.625 m/s².
Acceleration signifies the alteration of velocity over a specified duration. It can be calculated with this formula:

Where:
vf = final velocity
vi = initial velocity
t = time
Let’s examine the information provided in your query:
Initially, the vehicle was traveling at 25 m/s before coming to a halt. Thus, it was in motion and subsequently ceased moving, indicating that the final velocity is 0 m/s.
However, we notice that the problem does not provide a time value. We need to determine the time taken from when it was in motion to when it reached the traffic light located 20 m away.
The time can be calculated using the kinematics equation:

We derive the equation by substituting the known values first.




The duration from when it was in motion until it stopped is 1.6s. Now we can utilize this in our acceleration calculation.



It is important to note that the acceleration is negative, indicating the vehicle slowed down.
The electromagnetic spectrum spans from radio waves to gamma rays. The picture provided illustrates this entire spectrum. However, the optical telescope is limited to observing only the visible spectrum, which ranges from 400 nm to 700 nm. This segment reflects the colors of ROYGBIV, with red exhibiting the highest frequency and violet the lowest frequency.
This can be determined using the principle of energy conservation. The ski lift begins with a velocity of v= 15.5 m/s, and all of its kinetic energy Ek converts into potential energy Ep, thus we set Ep equal to Ek.
Because Ek is given by (1/2)*m*v², where m denotes mass and v represents speed, while Ep equals m*g*h, where m is mass, g is 9.81 m/s², and h is height. Now:
Ek=Ep
(1/2)*m*v²=m*g*h, canceling out the mass,
(1/2)*v²=g*h, rearranging for height by dividing by g,
(1/2*g)*v²=h and substituting the values:
h=12.245 m. The hill's height rounded to the nearest tenth is h=12.25 m.