Suppose a universe is spatially flat, and (at some moment in time) has density ρ. Suppose a creature living in one galaxy in this universe sees a second galaxy receding (at this same moment in time), with its spectral lines redshifted by a factor of z. How far away is the second galaxy from the first? (Note the distance is small enough that Hubble's law can be safely applied.) Values: ρ = 5x10-27 kg m-3 z = 0.10 Enter your answer in Mpc, rounded to the nearest integer.

Suppose a universe is spatially flat, and (at some moment in time) has density ρ. Suppose a creature living in one galaxy in this universe sees a second galaxy receding (at this same moment in time), with its spectral lines redshifted by a factor of z. How far away is the second galaxy from the first? (Note the distance is small enough that Hubble's law can be safely applied.) Values: ρ = 5x10-27 kg m-3 z = 0.10 Enter your answer in Mpc, rounded to the nearest integer.

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