The photons that make up the cosmic microwave background were emitted about 380,000 years after the Big Bang. Today, 13.8 billion years after the Big Bang, the wavelengths of these photons have been stretched by a factor of about 1100 since they were emitted because lengths in the expanding universe have increased by that same factor of about 1100. Consider a cubical region of empty space in today's universe 1.00 m on a side, with a volume of 1.00 m³. What was the length so of each side and the volume V of this same cubical region 380,000 years after the Big Bang? So = Vo = Enter numeric value Today the average density of ordinary matter in the universe is about 2.4 × 10-27 kg/m³. What was the average density po of ordinary matter at the time that the photons in the cosmic microwave background radiation were emitted? Po = m m³ kg/m³

The photons that make up the cosmic microwave background were emitted about 380,000 years after the Big Bang. Today, 13.8 billion years after the Big Bang, the wavelengths of these photons have been stretched by a factor of about 1100 since they were emitted because lengths in the expanding universe have increased by that same factor of about 1100. Consider a cubical region of empty space in today's universe 1.00 m on a side, with a volume of 1.00 m³. What was the length so of each side and the volume V of this same cubical region 380,000 years after the Big Bang? So = Vo = Enter numeric value Today the average density of ordinary matter in the universe is about 2.4 × 10-27 kg/m³. What was the average density po of ordinary matter at the time that the photons in the cosmic microwave background radiation were emitted? Po = m m³ kg/m³