I think your answer for first question is incorrect.
You can refer to the explanation in this link to craft your answer for both questions. Have to use key words like Water has a fixed volumeand cannot be compressed so when the bottle is squeezed, the water rushed into the dropper and compressed the air pocket inside the dropper, causing the water level in the dropper to rise.
http://indianapublicmedia.org/amomentof … ment-work/
As force and density is not in p4 syllabus, I wonder if just stating that “the dropper with the increased water level is now heavier than before when the water level was lower in the dropper, hence it sinks when the bottle is squeezed”, is acceptabl?. How come a two mark question?