please explain in each steps. Thank you

In the alternative, suppose in #4 that the business deal is that L is to receive all cash distributions until L received an amount equal to her capital investment, plus a preferred return of 4% annually on that investment (until distributed), before any cash is distributed to G. The partnerships cash flow distributions provisions (i.e., the waterfall) provide that

L is entitled to distributions in the amount of her initial contribution of $2000,

L is entitled to distributions equal to her accumulated preferred return,

G is entitled to her catch-up, a distribution equal to 20 of the sum of (ii) and (iii), and

The balance, if any, is to be distributed 80:20 between L and G.

1. How should the $100 gain on Blackacre be allocated?

2.Further question: In year 2, the partnership continues to hold Whiteacre, but does not otherwise engage in any tax significant transactions. How should the partnership take into account Ls 4% preferred return?