What are 2 advantages of hydroponics?

The diagram below shows the layers of a rock having a trilobite: a rock column labeled rock is shown. the column has three layers. the bottommost layer of the rock has one shaded rhomboid shape, the middle layer has a rhombus with a diagonal along with two identical organisms marked as, trilobite, in the key, the top layer has two semicircles. a key is shown on the right side of the diagram. the shaded rhombus is marked as a, the rhombus with the diagonal is marked as b, the semicircle is marked as c which statement about the rock fossils is true?

You sample a population of butterflies and find that 56% are heterozygous at a particular locus. what should be the frequency of the recessive allele in this population?

Why is there more biomass at the producer level that at the consumer levels ? how does this relate to the 10% rule ?