Molecules made by living organisms that contain lots of carbon atoms joined together?

Apart of the periodic table is shown. a portion of the sixteenth and seventeenth columns of the periodic table is shown. column 16 reads eight oxygen, 16 sulfur, and 34 selenium. column 17 reads nine flourine, 17 chlorine, and 35 bromine. which of the following elements is less reactive than the others? bromine (br) oxygen (o) selenium (se) sulfur (s)

How many trophic levels are there in the following food chain? phytoplankton - shrimp - perch - pike - osprey

The graph shows the solubility of several different salts in water, across a range of temperatures. according to the graph, which salt can dissolve at a concentration of about 60 g/100 cm3 of water at 40 degrees celsius?