The acceleration of the car is solved by subtracting the initial speed from the final speed then dividing the result by the elapsed time.
initial speed = 72 km/hr = 20 m/s
final speed = 0 m/s
elapsed time = 5 seconds
acceleration = (0 m/s – 20 m/s) / 5 s
acceleration = - 20m/s / 5 s
acceleration = -4 m/s^2
The new acceleration is 
Explanation:
We can answer this problem by applying Newton's second law, which states that:

where
F is the net force on an object
m is the mass of the object
a is its acceleration
The equation can be rewritten as

In this problem, the initial acceleration is

Later:
- The net force is tripled: 
- The mass is halved: 
Therefore, the new acceleration is:

which means that the new acceleration is 6 times the original acceleration, therefore

Learn more about acceleration:
brainly.com/question/9527152
brainly.com/question/11181826
brainly.com/question/2506873
brainly.com/question/2562700
#LearnwithBrainly
Answer:
Air at higher altitude is under less pressure than air at lower altitude because there is less weight of air above it, so it expands (and cools), while air at lower altitude is under more pressure so it contracts (and heats up).
Explanation:
Hope that helped
Answer: average annual rainfall, average annual temperatures, types of plants and animals native to the area
Explanation: the best way you can identify a biome is by telling which animal or species are native to the certain area