A car moving along a straight highway with a speed of `72 km h^(-1)` is brought to a stop within the distance of `100 m`. What is the retardation of the car and how long does it take for the car to stop ?

Explanation

To solve the problem, we need to find the retardation of the car and the time it takes for the car to stop. We'll use the equations of motion for uniformly accelerated motion.

### Step-by-Step Solution:

**Step 1: Convert the speed from km/h to m/s.**
- The initial speed \( U \) of the car is given as \( 72 \, \text{km/h} \).
- To convert km/h to m/s, we use the conversion factor \( \frac{5}{18} \):
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