Answer:
First Question 
 lower limit of 9 mph  
 upper  limit of 9 mph  
 
Second Question
lower limit of 120 pounds is  
 upper limit of 120 pounds is   
 
Third  Question
lower limit of 187 pounds is  
 upper limit of 187 pounds is   
   
Step-by-step explanation:
From the question we are told that 
   The amount of beer administered is  three 12-ounce beers
   The  amount of coffee administered is  two cups of coffee
   The  speed limit is   60-mph
   The smallest unit of scale is  1 mph
   The first subject scores 9 mph
Generally given that the smallest unit of scale is  1 mph then the deviation of  9 mph will be by 
Hence the lower limit of 9 mph is 
     
     
And  the upper  limit of 9 mph is
     
      
     
Generally given that the measuring weight on a scale that is accurate to the nearest 0.2 pound then 120 pounds will deviate by  
Hence the lower limit of 120 pounds is 
     
     
And  the upper  limit of 120 pounds is
     
      
    
Generally given that the measuring weight on a scale that is accurate to the nearest 0.5 pound then  187 pounds will deviate by  
Hence the lower limit of 120 pounds is 
     
     
And  the upper  limit of 120 pounds is
     
     