The answer to the first one is 72.
        
             
        
        
        
9514 1404 393
Answer:
   16832
Step-by-step explanation:
As your problem statement says, ...
   2104 × 8 = 4×8 +00×8 +100×8 +2000×8
   = 32 +0 +800 +16000
   = 16,832
 
        
             
        
        
        
The answer is 
h = AB sin tetha, 
tetha is <span>1 degree 10' = 1.1°, and AB = 3.5km
the vertical rise is h = 4.7</span>
        
             
        
        
        
if / means absolute value, then the answer is -3. The absolute value of 3 is 3, then you take the negative value of it, which is -3. 
Btw, the absolute sign is ||, not //.