Which statement best describes how scientists and engineers work together in the research and development cycle?
O A. Engineers make a new discovery about nature, and then scientists
do experiments to verify it.
O B. Scientists develop new technology, and then engineers use it to
solve design problems.
C. Scientists make a discovery, and then engineers use it to help
them solve problems with their designs.
D. Engineers develop a new technology, and then scientists use it to
solve design problems.

i think they are all correct

explanation:

they seem good

speed of light in vacuum is 300,000 km/s

speed of light in other mediums is given by the expression v = c/n, where c is the speed of light in vacuum and n is the refractive index of medium.

for the first medium v = 200,000 km/s

  so, refractive index of medium = 300000/200000 = 1.5

    1.5 refractive index is usually for glass. so first medium is glass.

for the second medium v = 250,00 km/s

so, refractive index of medium = 300000/250000 = 1.2

    1.2 refractive index is usually for water. so second medium is water.

for the third medium v = 0 km/s

so, refractive index of medium = 300000/0 = ∞

    ∞ refractive index is usually for opaque mediums. so third medium is opaque medium.