As of 2019, South African runner, Wayde van Niekerk, holds the world record in 400 m. He was able to maintain an average speed of 9.3 m/s. How long did it take him to run the 400 meters?

from 1609, galileo galilei used the recently invented telescope to observe the sun, moon and planets. he saw the mountains and craters of the moon, and for the first time revealed the planets to be worlds in their own right. galileo also provided strong observational evidence that planets orbited the sun.

his discoveries about the moon, jupiter's moons, venus, and sunspots supported the idea that the sun - not the earth - was the center of the universe, as was commonly believed at the time.galileo turned his gaze toward venus, the brightest celestial object in the sky - other than the sun and the moon.

answer: the correct answer id option(d).

explanation:

snell's law refraction:

the angle of refraction =

the angle of incidence =

refractive index of air = = 1

refractive index of glycerol = 1.47

from the given options, the most closest answer to 63.72° is 65° of option (d).

graphing motion: mastery test

209be

what is the instantaneous acceleration of

the particle at point b?

0 meters/second?

10 meters/second?

12 meters/second?

velocity imetersisecond

15 meters/second?

20

time (seconds)

answer: 0 meters/second^2

this could be newton#'s law of cooling. the cooling curve is exponential