4. It is an endothermic process. The body of someone taking a shower would be absorbing heat from the environment, another example of this would be cooking an egg
5. Ice melting is endothermic. The ice is absorbing heat from the environment, water freezing would be an exothermic reaction as it is transferring heat into the environment
6 however i do not have an answer for. I may just be a little dense but I'm not entirely sure what it is asking when it asks what the system is.