Final answer:
Approval for vehicle repairs above $50 typically involves the auto insurance company or the manufacturer in the case of warranty conditions. The provided statistics show that a $50 repair cost is well below the average incurred from crash tests, implying that such approval processes are standard practice.
Step-by-step explanation:
The question of who must approve vehicle repairs above $50 is not explicitly answered by the provided statistical reference regarding car crash-tested damage costs. However, it can vary depending on the context. If it is regarding consumer rights or insurance policies, often an auto insurance company must approve repairs above certain thresholds to ensure they align with the policy's terms. If it's within the context of a warranty, the manufacturer may need to approve repairs if they are covered under warranty terms.
As for the provided information indicating that 90 percent of crash-tested cars had damage repair costs of $1,700 or less, this suggests most tested cars will incur repair costs well above $50. It highlights that repairs costing $50 are relatively minor compared to average costs incurred from crash testing. Therefore, one could infer that the approval process for repairs over $50 is a common and necessary procedure in the context of auto insurance or warranty conditions.