Answer:
Critical angle is 24.4°
Explanation:
[tex]n \sin(c) = 1[/tex]
n is refractive index
c is critical angle
[tex]{ \sf{2.42 \times \sin(c) = 1}} \\ { \sf{ \sin(c) = \frac{1}{2.42} }} \\ \\ { \sf{ \sin(c) = 0.4132}} \\ { \sf{c = \sin {}^{ - 1} (0.4132) }} \\ { \sf{c = 24.4 \degree}}[/tex]
