Question

With process Plz！！Thank you very much

Answer 1

Step-by-step explanation:

In circle with centre O.

$OA \cong OB.. (Radii\: of \:same \:circle) \\\therefore m\angle OAB = m\angle OBA =28°\\(m \angle 's \:opposite \:to \:congruent \:sides \:\\are \:equal)$

$m \angle AOB = 180°-(m\angle OAB + m\angle OBA)\\\therefore\: m \angle AOB = 180°-(28° + 28°)\\\therefore\: m \angle AOB = 180°-56°\\\therefore\: m \angle AOB = 124°\\m \angle ACB = \frac{1}{2} \times m \angle AOB$

$(m\angle\: formed\: on\: the \:circle \:\\is\: half\: the\:\angle\: formed\: at\: the \:center\: \\of \:the \:circle)$

$\therefore\: m \angle ACB = \frac{1}{2} \times 124°\\\therefore\: m \angle ACB = 62°$