Please anyone help me dynamic quiz i need it for a test

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The discussion revolves around solving two physics problems related to motion and deceleration. For question 3, the key steps involve converting the initial velocity from 72 km/h to m/s, calculating the distance traveled during the reaction time of 0.6 seconds, and determining the stopping distance by subtracting this from 40 m. The required deceleration must then be compared to the deceleration due to friction to assess feasibility. The second problem involves concepts from Newton's 2nd law and pulley systems, with references provided for further understanding. Understanding these principles is crucial for successfully answering the test questions.
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http://www.filefreak.com/pfiles/38439/physics.JPG

need help on question 3 and 4

I don't understand what to do for those question can anyone show me an message below
 
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In problem 3, one has a distance of 40 m in which to react then decelerate to a stop.

One knows the initial velocity 72 km/h (and one should convert to m/s) and a time of 0.6 s, during which some distance is traveled, dreaction. The distance over which the car must decelerate is 40 m - dreaction = dstopping

One has to determine if the required deceleration exceeds the acceleration (or deceleration) associated with force of friction.

Reference for equations of motion
http://hyperphysics.phy-astr.gsu.edu/hbase/mot.html

For the pulley problem (or equivalent) -
http://hyperphysics.phy-astr.gsu.edu/hbase/hpul.html#c1

General problems for Newton's 2nd law -
http://hyperphysics.phy-astr.gsu.edu/hbase/N2st
 
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