Describe the following question

Question 1- Calculate the average distance of the electron to the nucleus in a H-atom in the 2s and 2p states. Which do you expect to be greater and why?

Question 2- The spherical harmonics can be represented visually by sketching on a unit sphere which regions are positive and which are negative. Note each point on the surface of the unit sphere corresponds to a particular coordinate (x, y). In this way, sketch the spherical harmonics Ysub0super0(x, y) and Ysub1super0(x, y).

Question 3- A node of a wave function is a surface where the wave function (and hence probability density) is zero. Calculate and sketch the nodes of the 2s and 2p states. Is this consistent with your knowledge of the shape of these orbitals?

I need help to explain the above question.