4 x 108ms-1
2.25 x 108ms-1
\(\frac{4}{9}\) x 108ms-1
2.25 x 102ms-1
4.33 x 108ms-1
Correct answer is B
Air to water = \(\frac{\text{speed in air}}{\text{speed in water}}\)
\(\frac{4}{3}\) = \(\frac{3 \times 10^8}{V}\)
4V = 3(3 x 108)
V = \(\frac{3(3 \times 10^8)}{4}\)
V = 2.25 x 108ms-1