Several companies produce personal water filters that can travel anywhere. Such filters make any water safe to drink by removing bacteria and other contaminants. However, they cannot filter heavy metals and viruses or remove salt. The filters are constructed of sturdy plastic and weigh just two ounces. They can be purchased in stores or online for about $20. Evaluate this design by describing the criteria it does or does not meet.
layer a is the exosphere and layer b is the thermosphere. is the answer i think but i hope this .
the minimum amperage that the current in this wire would have to have so that its weight is completely supported by the magnetic force due to earth's field, assuming that no other forces except gravity act on it