Answer:
Part a)

Part b)

Explanation:
As we know that there is no external force on the system of two masses so here total momentum of the system will remains conserved
so we can say




Part b)
magnitude of the initial speed of A = 
magnitude of the initial speed of B = 
magnitude of final speed of A = 
magnitude of final speed of B = 
Now change in total kinetic energy is given as



What is the magnitude of force required to accelerate a car of mass 1.7 × 10³ kg by 4.75 m/s²
Answer:
F = 8.075 N
Explanation:
Formula for force is;
F = ma
Where;
m is mass
a is acceleration
F = 1.7 × 10³ × 4.75
F = 8.075 N
Answer:29 electrons
Explanation: If you look on a periodic table, the atomic number is the amount of electrons it has.
The quantity of matter in a body regardless of its volume or of any forces acting on it.
Send wave from your location to the object and wait until echo is back.
Measure the time taken.
If you know the speed of wave (say sound wave), than just multiply by half time taken wave to return