A student is provided with a sample of a gas and asked to identify it. He knows that the gas is either chlorine, oxygen, carbon dioxide or hydrogen. Describe how the student should analyse the gas in order to identify it. Describe the tests that he should do, and how he should interpret his observations

Which process is involved in growing crops? irrigation transportation recreation condensation

Asmall number of finches are removed randomly from the wild and placed in a protected bird area. they are given as much food as they need and have plenty of space. why would natural selection not occur in this population? a. there is no reason for genetic mutation to occur. b. the birds compete for limited resources, c. the population has not reached carrying capacity. d. there is no genetic variation in the finches.

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