Which best compares and contrasts how John Newlands and Dmitri Mendeleev organized elements?
A. Both Newlands and Mendeleev arranged elements according to their chemical properties, but only Newlands used atomic
mass as well
B. Both Newlands and Mendeleev arranged elements according to their atomic masses, but only Mendeleev used chemical
properties as well.
C. Both Newlands and Mendeleev organized elements into groups, but only Newlands used a table with rows and columns
D. Both Newlands and Mendeleev organized elements into a table with rows and columns, but only Mendeleev named different
groups of elements.

total distance travelled = 60 miles

total time taken =1.5 hours

average speed = total distance / total time

60 / 1.5

= 40

therefore, average speed = 40 m/h

happy to

pls mark as brainliest

c

explanation:

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.

god i hope this !