Final answer:
If you are in IMC and experience two-way radio comms failure, without exercising emergency authority, you should follow the procedure of using alternative communication channels and informing higher authorities.
Step-by-step explanation:
If you are in IMC (Integrated Marketing Communications) and you experience a two-way radio comms failure, and you choose not to exercise emergency authority, you should follow the procedure of using alternative communication channels. This could involve trying to establish communication through other devices such as a cellphone, landline, or computer. In addition, you should also inform your supervisor or higher authorities about the radio comms failure and the steps you have taken to mitigate the situation.