Two indicators that will help you in determining which way to mount bite-wing radiographs are (1) the curve of Spee curves toward the distal, and (2) mandibular molars have distinct roots.

The correct answer is - upward, two.

Explanation:

The bitewing radiograph (BW) is a radiography image that is used to see the crowns of the maxillary and mandibular teeth, the interproximal surfaces of the teeth, and identifying interproximal caries.

The curve of the spee is also can be seen and mount with this image the curve of the spee is start at the tip of the lower canine, rn with the buccal cusp tips of the premolars and molars and continuing to the anterior end of the ramus. it is  2-D and upward from distal. It also shows that mandibular molar teeth have two distinct roots.

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