PLEASE HELP MAKE THIS A FOOD WEB

Check all that apply diatoms are marine algae that have a shell made of silica, what are some of the uses of the silica shell after the diatoms die? 1.the shells make up the diatomaceous earth used in filters 2.it can be used as an ingredient in abrasives 3.they are used in food products 4.the shells can be used in some insulating materials

What must be true for natural selection to heppen

What element is able to combine with itself and hydrogen to form large molecules ?