Answer:
The frequency of sound heard by the boy is 1181 Hz.
Explanation:
Given that,
Frequency of sound from alarm 
Speed = -8.25 m/s
Negative sign show the boy riding away from the car
Speed of sound = 343
We need to calculate the heard frequency
Using formula of frequency

Where,
= frequency of source
= speed of observer
= speed of source
= speed of sound
Put the value into the formula

here, source is at rest


Hence, The frequency of sound heard by the boy is 1181 Hz.
Theories are usually backed up with a lot of evidence. If the evidence is well studied then it is useful information.
Answer:
<h2>The amount of torque put on the car is 33,000Nm</h2>
Explanation:
Formula for calculating torque is expressed as T = rFsin
where;
r is the radius of the of the arm of the jack = 3m
F is the force exerted = 11000
is the angle of rotation = 90°
On substituting;

Mechanical energy = potential energy + kinetic energy
The ball is on the ground so it has no potential energy. that's all i know.
1.could be anything... make sure there is safety nets below in case of an accident?
2. F1 car is more stable because the center of gravity is lower than the double deckers center of gravity
3. To find the mass of an object just put it on the scale, to find the volume put the object in a marked beaker to measure the water displacement which is the volume