MCQOPTIONS
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| 1. |
At least how many galaxies are there in the observable universe as estimated from Hubble XDF data? |
| A. | <100000 |
| B. | Between 100000 and 1 million |
| C. | Between 1 million and 100 billion |
| D. | Between 100 billion and 1 trillion |
| Answer» E. | |