Answer:
Option A is correct
Explanation:
Direction of spin can be measured because of the behaviours of the particle as it goes through a magnetic field and the size of the spin is dependant on type of particle.
Answer:

Explanation:
Here we know that initial temperature of ice is given as

now the latent heat of ice is given as

now we also know that the mass of ice is

so here we know that heat required to change the phase of the ice is given as



In atoms, electrons surround the nucleus in specific energy levels.
Answer: Option B
<u>Explanation:
</u>
Atom, actually considered as the tiny part that is ever present in this universe. Many theories and experiments were conducted, for studying what was present inside of an atom, and many theories came into light.
And finally, Bohr-Sommerfeld Theory stated the final conclusion, that the positive charge is at the centre of the nucleus, and all the electrons revolve in their specific energy levels. If an atom wants to move to lower energy state, it should emit energy, whereas for going to higher state, it should gain energy.