Which lipid is the main component of cell membranes

What is the "great pacific garbage patch"? (a) a large area of marine debris concentrated by rotating ocean currents (b) a large area around the pacific rim where debris collects from natural disasters such as tsunamis (c) an area in the pacific ocean where trash is intentionally dumped due to lack of landfill availability (d) a large trash dump located in hawaii

Why are shark population in decline worldwide?

This is a 2017 topographic map of puerto rico in the united states, and i'm sorry that people there have suffered such a disaster. i want to ask, what do the yellow dots and areas represent on this graph? and the blue area and the little blue circle, and the little blue sign that looks like a signal tower, what do they stand for?