I think the correct answer among the choices listed above is option B. Silicon oxide is the solid that contains two types of bonds because you have Si-Si bonds and Si-O bonds. That is two different covalent bonds. Hope this answers your question.
5 ml=5 cm³ , density=mass/volume=45/5= 9 g/cm³ therefore answer B
Cell theory states that all the living organisms are made up of basic structural and functional units, cells. All cells divide and give rise to new cells. All the cells have similar chemical composition. The nuclei acid DNA present in the chromosomes helps in carrying hereditary information from generation to generation. So, in order to sustain life the cells must contain DNA either enclosed in the nucleus or freely floating in the cytoplasm.
