<ABC would equal 106
seeing in triangle ABD angle A equals 67 you would multiply that by 2 and then subtract it from 180 to get 46, and then triangle DBC all the angles would equal 60. so then add 46 to 60 to get 106 the measure of <ABC
B; 25.65+13.23+6.35=45.23
To do this mentally just add the 2 decimals places together first (1.23). Then just add the whole numbers (44). Then add the 2 numbers together, 44+1.23=45.23
Option C: The solution set is 
Explanation:
The expression is 
Now, let us find the solution set.
Switch sides, we get,

Dividing by 2 on both sides, we have,

Thus,
Hence, the above expression becomes,

Simplifying, we get,

Applying the log rule, we get,

Simplifying, we have,

Applying the log rule, we have,

Thus, the solution set is 
Hence, Option C is the correct answer.
Answer:
Yes
Step-by-step explanation:
They are exact and you can't mess up or accidentally slide the compass or straightedge around. This is just my opinion though.
Y=2
EXPLANATION:
2(-10)-9y=-38
-20-9y=-38
-9y=-18
y=2