Points A,B,C and D lie on a circle. The chord AB subtends ∠ACB=40∘ at point C and ∠ADB=4x−20∘ at point D on the same side of AB. The chord AC subtends ∠ABC=3x+5∘ at point B.
(i) Find the value of x.
(ii) Calculate ∠ADB and ∠ABC.
(iii) Hence, determine the measure of ∠ADC.