First, find the arc measure BD. The arc measure is twice the central angle measure. BD should be 48*2 = 96.
The chord BC looks like it’s the diameter of the circle, so it must have a measure of 180.
From here you can find DC. The total measure of a circle is 360.
360- 96-180 = 84, so DC is 84.
DBC is 360- DC
so 360- 84 = 276.
DCB is just 360- BD
so 360- 96 = 264.
Hope this helps!