If you walk for 1.5 hours and travel 7.5km, what is your speed?

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

If scientists are wrong about earth's age based on radioactive material and the decay rates are really much faster, how would nuclear power plants be affected?

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