A controlled experiment is when scientests go throw thests to make an experiment
The position-time graphs show the relationship between the position of an object (shown on the y-axis) and the time (shown on the x-axis) to show velocity.
<h3>What is velocity?</h3>
Velocity is a vector quantity that tells the distance an object has traveled over a period of time.
Displacement is a vector quality showing total length of an area traveled by a particular object.
Imagine a time-position graph where the velocity of an object is constant. What will be observed on the graph concerning the slope of the line segment as well as the velocity of the object?
The slope of the line is equal to zero and the object will be stationary.
The position-time graphs show the relationship between the position of an object (shown on the y-axis) and the time (shown on the x-axis) to show velocity.
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The acceleration of the car is 0.8049
.It takes 13.802s to travel the 230 m.
<h3>
What is acceleration?</h3>
In mechanics, acceleration refers to the rate at which an object's velocity with respect to time varies. Acceleration is a vector quantity (in that they have magnitude and direction). The direction of an object's acceleration is determined by the direction of the net force acting on it. Newton's Second Law states that the combined effect of two factors determines how much an item accelerates:
(i) It follows that the magnitude of the net balance of all external forces acting on the object is directly proportional to the magnitude of this net resulting force, and
(ii) the mass of the thing, depending on the materials out of which it is constructed, is inversely proportional to the mass of the thing.
Calculations:
40 km/hr ----- 11.11m/s
80 km/hr ----- 22.22m/s

Time taken
v-u=at
22.22-11.11= 0.8049 x t
t=13.802s
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Answer:
low risk for tissue damage
uses radio waves
the last three are not correct
:)