Final answer:
If the premiums for a policy will be increased by more than 15%, the insured must be given a warning. The time frame for this warning can vary depending on the insurance company and policy, but it is common for insurers to provide at least 30 days' notice before implementing a premium increase.
Step-by-step explanation:
If the premiums for a policy will be increased by more than 15%, the insured must be given a warning. The question does not specify a specific time frame for this warning, so it can vary depending on the insurance company and policy. However, it is common for insurers to provide at least 30 days' notice before implementing a premium increase.