During science class, while studying mixtures, you mix together table salt and sand. your teacher challenges you to separate the salt from the sand. what property could you use and how would you use it? a) solubility; add water to the mixture and dissolve the salt. b) density; the two will form two layers. scoop out the top layer. c) color; pick out one of the two solids by using color to guide you. d) particle size; pour the mixture through a paper filter to separate the two.

African penguins, which inhabit the coasts of southern africa, were classified as an endangered species in 2010. two significant threats to their survival are ecosystem damage from oil spills and overfishing by humans. overfishing depletes the food supply of african penguins. the best method to reduce the threat of overfishing would be to . the risk of oil spills could be reduced by increasing the use of , which should oil consumption. if an oil spill does occur, could be used to remove the oil so the ecosystem may more quickly recover.

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

3differences between bacteria and other 2 cells