【Range】 ,  【gamut】 ,  【reach】 ,  【radius】 ,  【compass】 ,  【sweep】 ,  【scope】 ,  【orbit】 ,  【horizon】 ,  【ken】 ,  【purview】  can denote the extent that lies within the powers of something to cover, grasp, control, or traverse.

【Range】 is the general term indicating the extent of one’s perception or the extent of powers, capacities, or possibilities.

【Gamut】 suggests a graduated series running from one possible extreme to another.

【Reach】 suggests an extent of perception, knowledge, ability, or activity attained to or experienced by or as if by stretching out.

【Radius】 suggests a usually circular area (as of activity) implied by a known or determined center.

【Compass】  implies an extent, sometimes more limited than that suggested by  【range】 , of perception, knowledge, or activity; it is likely to connote a bounding circumference.

【Sweep】 suggests extent, often circular or arc-shaped, of motion or activity, which latter notion it more strongly suggests than the preceding terms.

【Scope】 is applicable to an area of activity, an area predetermined and limited, but an area of free choice within the set limits.

【Orbit】 suggests a 【range】 of activity or influence, often circumscribed and bounded, within which forces work toward accustoming, integrating, or absorbing.

【Horizon】 suggests an area, perhaps arc-shaped or semicircular, of knowledge, interest, perception; it may suggest the new or the potential or envisioned.

【Ken】 tends to apply to personal or individual 【range】 of perception or cognizance.

【Purview】 may indicate either 【range】 of perception or knowledge or 【range】 of authority or competence.