An old woman is worried about time. She walks at a rate of 2 meters per second and travels a distance of 454 meters. How long does it take her to complete the motion?

Please help ASAP

227 seconds.

Explanation:

Speed is equal to distance divided by time. s = d/t

We can rearrange this algebraically to solve for the time it will take to cover a certain distance at a certain speed. Time is equal to distance divided by speed.  t = d/s

Then we substiture our known values for the variables and solve for our unknown.

t = 454m / 2m/s = 227s

If the lady is traveling 2 meters per second and she travels 454 meters then you will have to divide 454 by 2 to get the amount of time she walked.

454 divided by 2 = 227

This means that the lady traveled for 227 seconds or about 3.78 minutes.

d. platinum would have the greatest temperature increase because it has the lowest specific heat.

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.