So you question is most likely about a triangle DEF with the 3 angles being named D, E, F. The triangle would look something like the image attached below.
If that is what is being asked then i need more info to answer but 
By Definition it would be 180 degrees. 
 
        
             
        
        
        
11 school days are left. 
In the attached picture of a calendar, I marked the days the person has left. There are 11.
 
        
             
        
        
        
Kim did. Make the fractions into decimals(4 divided by 5, 6 divided by 10) Kim got 0.8, while Grace got 0.6.
        
             
        
        
        
Answer:
3rd option
Step-by-step explanation:
x < 7
means that x cannot equal 7 but all values less than 7
since not equal at either end of interval use parenthesis, not brackets , then
(- ∞ , 7 ) ← is the required interval
 
        
             
        
        
        
15 percent of the fruit in the fruit bowl are oranges