c$.$ Heterogeneous mixture:

mixture of salt and sugar

mixture of water and acetic acid

mixture of water and benzene

mixture of water and potassium chloride

mixture of sand and iron filings

mixture of hydrogen and oxygen

d$.$ Homogeneous mixture:

mixture of salt and suger

mixture of water and acetic acid

mixture of water and benzene

mixture of water and potassium chloride

mixture of sand and iron filings

mixture of hydrogen and oxygen