"Nuclear stability is based on (choose all that apply)
the ratio of protons to neutrons
the number of valence electrons
the ratio of protons to electrons
the size of the nucleus
the amount of energy in the nucleus"

the ratio of protons to neutrons

Explanation:

Nuclear stability is based on the ratio of protons to neutrons. The nuclear space is made up of protons and neutrons that occupies the nucleus of an atom.

For every atomic nucleus, there is a specific neutron/proton ratio which ensures the stability of the nucleus.

For sodium, Na, the neutron/proton ratio for stability is 12/11.

Any nucleus with a neutron/proton combination different from its stability ratio will be unstable.

weight of the box is given as

here this is placed on the inclined of angle 42 degree

now this weight will have two components one is along the incline other is perpendicular to it

so here we need to apply a force parallel to incline opposite to its component of weight

so here the component of weight is given as

here we have

so it requires 75 n force to move it upwards