Final answer:
The recommended ratio for resuming CPR after delivering one shock with an AED is 30 compressions to 2 breaths. The compressions technique should be the two thumb encircling hands technique.
Step-by-step explanation:
To resume CPR after delivering one shock with an AED, the recommended ratio is to perform 30 compressions followed by 2 breaths. The compressions technique used should be the two thumb encircling hands technique. This involves placing both thumbs side by side on the lower half of the sternum, with the rest of the fingers supporting the back.