Answer:
i can only answer the compounds and elements, because im not quite sure on the mixtures!
Elements and compounds are alike because they are both pure substances but elements consist of only one atom i.e. one oxygen atom, one carbon atom.
Compounds have two types of atoms like CO2 for example it has a carbon atom and two oxygen atoms
Here is an equation
Carbon plus oxygen equals carbon dioxide
i hope this has helped a bit for you!!
slight mistake sorry
thats why it is CO2. lol he's right!!