49. Where is a visitor advised to park his car if he'll spend several hours at the Museum?

• A、In a garage provided by the Museum. 
  
  

• B、On a parking space near the Museum. 
  
  

• C、On a metered parking space on the street. 
  
  

• D、In a public garage at one end of Old Sacramento. 
  
  

45. When is it bad to eat sweets and ice-cream?

• A、When we are hungry.
  
  

• B、When we want to.
  
  

• C、After the meal. 
  
  

• D、Before the meal. 
  
  

51.(      )