Answer:
82.1 km
Explanation:
We need to resolve each displacement along two perpendicular directions: the east-west direction (let's label it with x) and the north-south direction (y). Resolving each vector:

Vector B is 48 km south, so:

Finally, vector C:

Now we add the components along each direction:

So, the resultant (which is the distance in a straight line between the starting point and the final point of the motion) is

Here are the answers to the question. Make sure to give a valid reason, please.
A. the sum of the protons and neutrons in one atom of the element.
B. a ratio based on the mass of a carbon-12 atom.
C. a weighted average of the masses of an element's isotopes.
D. twice the number of protons in one atom of the element.
Increased by a factor of 4
Answer: F = 1235 N
Explanation: Newton's Second Law of Motion describes the effect of mass and net force upon acceleration: 
Acceleration is the change of velocity in a period of time: 
Velocity of the car is in km/h. Transforming it in m/s:

v = 13 m/s
At the moment the car decelerates, acceleration is
a = 65 m/s²
Then, force will be

= 1235 N
The horizontal net force the straps of the restraint chair exerted on the child to hold her is 1235 newtons.
I think the answer maybe C