<span>The crust (sedimentary/igneous/metamorphic rocks), the mantle (oxygen, silicon, magnesium, iron) , inner core (solid iron and nickel) and outer core (liquid iron and nickel). </span>
No. caffeine is perfectly fine for children. I have it often and I'm 13. I only use it to an extent though. I think that its perfectly fine for kids to use caffeine just not too much! And this is absolutely NONE of the governments concern, they know too much about us already...
Answer:
The principal functions of the gastrointestinal tract are to digest and absorb ingested nutrients, and to excrete waste products of digestion. Most nutrients are ingested in a form that is either too complex for absorption or insoluble, and therefore, indigestible or incapable of being digested.