Text-1 Read the text. Then choose the correct answer for questions 1-2

70. Why do helicopters not need runways.
A) they are smaller than planes.
B) they can fly backward.
C) They can take off without moving forward.
D) They can hover in the air.
71. What does the word conventional in the text refer to?
A) delete B) created for the first time
C) tradition D) for a large group of people
72. How are helicopters used as ambulances?
A) They lift trees out of forests.
B) They airlift people not of accident.
C) They chase suspects on the ground.
D) They can drop water on fires.