What are the four conditions for the binomial setting?

The four specific conditions for a binomial setting which will produce a binomial distribution are as follows: 1) each observation falls into one of two categories which is known as a success or failure 2) there is a fixed number of observations 3) the observations are all independent 4) the probability of success (p) for each observation is the same 

A. p = 2(l + w)p/2 - l = ww = p/2 - l b. while isolating the variable w in the equation, i first divided both sides by 2 and then i subtracted l from both sides. i hope this .