∠DBC = 19° since the two angles have to add up to 180, if x = 23, then 23 -4 = 19 for the right, and 7 x 23 = 161, and 161 + 19 = 180.
Answer:
Step-by-step explanation:
Area of a sphere is 
let d be the diameter of the moon and D be the diameter of the earth
d = 1/4 D
Area of Earth = 
Area of moon = 

Unit rate = price/quantity
= 40/16
=2.5 per pair (2.5/1)