Which type of pollution is believed to have the most impact on a ecosystem

Which organism is the producer in this food web? 7th grade question. a) arthropods b) birds c) fungi d) plants

Describe five factors that influence the value of fuel

The table shows dates and appearance of index fossils. which rock layers can be dated most precisely? a) a layer containing both a fossil 4 and a fossil 3 b) a layer containing both a fossil 2 and a fossil 3 c) a layer containing both a fossil 1 and a fossil 4 d) a layer containing both a fossil 1 and a fossil 2