The configurations of eight compounds A through H are shown below, using various kinds of stereo-representations. To answer the four questions posed below, enter letters (A through H) indicating your choice(s) in the designated answer box. If no structure satisfies the conditions of the question enter an X.

Enter letters corresponding to your selection(s) or an X for none in each answer box.
Do not enter punctuation (eg. commas or semicolons) or spaces.

1. Which if any of these configurations are achiral? .........  
2. Which if any of these configurations has no stereogenic center? ....  
3. Which if any of these configurations has more than one stereogenic center? ..  
4. Which if any of these configurations are meso compounds? .......  

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Proceed to Part 2.