how do I get photos from Asus Andriod tablet on to a SanDisk ultra32Gb card.

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According to this site:

Asus Google Nexus 7 - Full tablet specifications

Your tablet doesn't allow for any external memory.

Source Quote:

MEMORY Card slot No
Internal 8/16/32 GB, 1 GB RAM

However and instead, try opting for a USB flash stick used as an external storage option.