Yes it will help you with c and d
Answer:
a subatomic particle of about the same mass as a proton but without an electric charge, present in all atomic nuclei except those of ordinary hydrogen.
B because it sets the scene and describes what it is like!
The Van der Waal’s forces are the forces, which are formed by the attraction of two opposite charged bodies. This charge exists due to the formation of the dipoles in the molecules or atom. The dipoles formed due to the movement of the electron in the atoms. The strength of the dipole or Van der Waal attraction depends on the size of the atoms or the molecule. As the size increases, the strength of the Van der Waal force increases. The positive and the negative regions are shown in the attached picture.
The cells present in the tail of the tadpole undergo a programme cell death. This is made possible when the organelles called lysosomes present in the cells break open to cause the breakdown and digestion of all the components of the cells. The lysosomes are break open only when the cells receive a signal from their neighbouring cells to undergo apoptosis, a process where the cell kills itself.