This has to do with refraction of waves

Please help answer all of the questions, i have provided the table that might be needed to answer the last couple questions just in case

Index of Refraction Index of Refraction Substance Substance (n) (n) Vacuum 1.0 Sodium chloride 1.53 Air (0 C, 101.325 kPa) 1.0003 Glass (crystal) 1.54 Water 1.33 Ruby 1.54 Ethyl alcohol 1.36 Carbon disulfide 1.63 Oleic acid 1.36 zircon 1.92 Quartz 1.46 diamond 2.42 Glycerin 1.47 Silicon 3.50 Lucite or Plexiglass 1.51 Lead sulfide 3.91 Glass (crown) 1.52