1- Notice that it's a right triangle (inscribed in 1/2 circle)
Then 2x+3x-5 + 90°° =180°===> x=10°
2- the 2 cords are equal then the triangle is isosceles & one these angle is equal to 95/2 = 47.5°°. Then 2 x 47.5 + x=180 ==> x =85°
3- Internal angle to a cercle: 88°=(x°+44°)/2===>66°
4- External angle to a cercle: x° = (160°-15°)/2===>72.5°
