Please provide clear and detailed steps so I can compare my work

Problem 2: A layer of oil with density 2=700kg/m3 floats on top of a volume of water with density 3=1000kg/m3. A block floats at the oil-water interface with 1/3 of its volume in oil (d=L/3) and 2/3 of its volume in water, as shown in the figure below. a) (3 points) By applying force balance on a solid block, calculate the density of the block, i.e., 1 ? b) (2 points) If 1=850kg/m3, what percentage of its volume would be in oil? 1 c) (3 points) If 1=850kg/m3 and we exchanged water with another fluid such that 3=800kg/m3, what percentage of its volume would be in oil