Observe the following figure and complete the following activity `:`
`/_ ABC " is " 90^@`

Explanation

Seg AC is the diameter
`:. M = (arc AMC ) = 180^(@)`
`/_ ABC = (1)/(2) m ( arc square ) ` …..(Inscribed angle theorem )
`:. /_ABC = (1)/(2) xx square `
`:. /_ABC = square `
`:. ` Angle inscribed in a semicircle is a `square `.
Activity `:`
Seg AC is the diameter
`:. `m ( arc AMC ) `= 180^(@)`
`/_ ABC = (1)/(2) m (arc AMC ) ` ...(Inscribed angle theorem )
`:. /_ABC = (1)/(2) xx 180^(@)`
`:. /_ABC = 90^(@)`
` :.` Angle inscribed in a semicircle is a right angle.