If your answer includes a decimal, please write your answer with a value through the hundredths place, $($i$.$e$.0\mathrm{.}00).$

a$.$ What is the substance on the top? Answer $1$ Question $1$

b$.$ What is this substance's index of refraction, n$?$Answer $2$ Question $1$

c$.$ What is the substance on the bottom? Answer $3$ Question $1$

d$.$ What is this substance's index of refraction, n$?$ Answer $4$ Question $1$