Place successively and independent of each other 20 particles into 10 boxes. Hereby, each of the 10 boxes is chosen with the same probability.

a) Determine the probability of the following events
1. Exactly one particle is in box 1.
2. At least one particle is in box 1.

b) Give the approximated values of the above probabilities using a suitable Poisson Distribution

c) What is the probability that there are exactly two particles in each of the 10 boxes?

If someone could help me I'm struggling to approach each problem