1, => to find m<BAC=1/2 of measure arc Bc
=>m<BAC=72°÷2
=>m<BAC=36°
2, •to find measure arc AB
first we have Arc AD =142° so the center of the circle is equal with it.
• and we have measure arc BC =72°the circle is equal with it.
so let say that the center is [o] then <AoB=measure arc BC that means it measures 72° so arc AB is 72°
I hope it helps and if I am wrong please send messages
