"The space shuttles is the subject."
Simple formula: find the verb of the sentence then ask the question "who or what performs the verb" and the answer to that question is the SUBJECT of that sentence!
In your sentence; ask the question; 
"Who or what have made travel to the International space station convenient and possible?
Answer: The space shuttles (that's your subject)
        
             
        
        
        
B) poor in the Williamsburg section of Brooklyn. 
 
        
                    
             
        
        
        
In an effort to reduce the turnover of Nurses, your hospital started
a program to conduct exit interviews with all Nurses who voluntarily left the hospital. The primary purpose of the exit interviews was to determine specific reasons for leaving.
        
             
        
        
        
Answer:
Some of the questions are unclear.
4. ... money in my pocket because I am afraid <u>of losing it. </u>
5. ... finish on time <u>in spite of</u> our best efforts. 
6. Help <u>yourself </u>to some cookies!
7. Helen's never late so she<u> must </u>be held up in traffic. 
8. Randy succeeded<u> in qualifying</u> for the 100 m sprint. 
9. Northern Europe's economies are heavily<u> dependent on</u> natural resources. 
10.<u> At first I</u> didn't look forward to exercising at the gym, but now I really enjoy it. 
11. If you'd been more attentive, you <u>would have heard</u> what the teacher was saying. 
12. As soon as Sarah<u> comes </u>in, ask her to help you. 
 
        
             
        
        
        
Answer:
The situational irony was that both of them were in acceptance and denial mode.
Explanation:
The aunt and the children were trying their best to remain in their position as far the situation persists. Since the entry of a housefly in the scene made the situation rather dramatic. The children seems to be quite aggressive in pestering with the housefly. However, the aunt wants to keep herself cool. She continues to persuade the children in her own way of not to distrub that poor creature in any way.