Answer:
Newton's Cradle is a neat way to demonstrate the principle of the CONSERVATION OF MOMENTUM.
What happens here is when the ball on one end of the cradle is swung and it hits the other balls that are motionless, or stationary, the momentum of the swinging ball is transferred to the next ball upon impact.
Momentum is not lost in this action, what happens when it hits the next ball, the momentum is transferred to the next one, and then the next, and the the next, till it reaches the last ball on the other end. Since nothing is next to the last ball, it pushes the ball upwards, which will swing down and repeat the process going the other way.
This also demonstrates the CONSERVATION OF ENERGY. As you will see, the energy continues to move through the other balls, passing it from one ball to the other, which keeps this constantly moving.
B
Electrons are found in shells or orbitals that surround the nucleus of an atom

The emission spectrum of a chemical element or chemical compound is the spectrum of frequencies of electromagnetic radiation emitted due to an atom or molecule making a transition from a high energy state to a lower energy state. The photon energy of the emitted photon is equal to the energy difference between the two states. There are many possible electron transitions for each atom, and each transition has a specific energy difference. This collection of different transitions, leading to different radiated wavelengths, make up an emission spectrum. Each element's emission spectrum is unique. Therefore, spectroscopy can be used to identify elements in matter of unknown composition. Similarly, the emission spectra of molecules can be used in chemical analysis of substances.
5 hope this helps I’m pretty sure it should be right