The correct answer to the problem is shown, but I do not know how they arrived to the answer.

edule PHYS1420 (2022) - Go Course Home /course.html?courseld=170928528OpenVellumHMAC=40abb62eb3bc751ec80e3ab0244e877a# 10001 Part A A beaker contains a thick layer of oil (shown in green) of density p2 floating on water (shown in blue), which has density pa A cubical block of wood of density pi with side length L is gently lowered What is the distance d between the top of the wood cube (after it has come to rest) and the interface between the oil and water? into the beaker, so as not to disturb the layers of liquid, until it floats peacefully between the layers, as shown. (Figure 1) Express your answer in terms of quantities given in the problem introduction. >View Available Hint(s) d = (P1-P3) L P2 P3 Previous Answers Correct In solving this problem, there is an implicit assumption that 0