Question

If m 13 years ago

Answer 1

you can have any length for arc GJI, by scaling the circle keeping inscribed angle fixed.

question is wrong, it should be :

If m<GJI=78, calculate the measure for arc GJI.

Answer 2

then,

you can use the relation,
central angle = 2* inscribed angle

you may get smthng like,

GJI = 360 - 2*78