Answer:
The value of given expression is 13 / 3
Step-by-step explanation:
Given expression in the form of improper fraction;
17/3 - 
Find;
The value of given expression
Computation:
⇒ 17/3 - 
Step 1 ;
Change mixed fraction into simple fraction
⇒ 17/3 - 4/3
Step 2 ;
By taking LCM of denominators;
⇒ [17 - 4] / 3
Step 3 ;
Subtract 17 from 3
⇒ [13] / 3
The value of given expression is 13 / 3
I believe that it is the second and third boxes
Answer
Step-by-step explanation:
Law of sines: SinB/15 = SinA/BC
B = 90
A = 180-90-21=69°
BC= (15*SinA)/SinB = (15*sin69)/1 ≈ 14m