49. Among the giant ocean mammals \_\_\_\_\_, which may weigh up to 180 tons and measure 98 feet in length. (A) the blue whale (B) has the blue whale (C) being the blue whale (D) is the blue whale

55. Freezing foods \_\_\_\_\_ the spread of bacteria, fungi, or other microorganisms even though the process does not sterilize them. (A) retards (B) retard (C) to retard (D) is retarded III. Complete each paragraph below by filling in the blanks with correct answers. The exploration of space required the development of rockets that would be able to attain sufficient (56) to achieve extreme altitudes. In order to escape from Earth's (57), a rocket has to achieve a speed of 40,000 kph (25,000 mph), which requires a very powerful engine and a great deal of fuel. Even with the most powerful engine available, it would not be possible to (58) sufficient (59) to lift a rocket and all its fuel to the required (60). To solve this, scientists developed the multi-stage rocket.

49. Among the giant ocean mammals \_\_\_\_\_, which may weigh up to 180 tons and measure 98 feet in length.
(A) the blue whale
(B) has the blue whale
(C) being the blue whale
(D) is the blue whale

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相關試卷

49. Among the giant ocean mammals \_\_\_\_\_, which may weigh up to 180 tons and measure 98 feet in length.(A) the blue whale(B) has the blue whale(C) being the blue whale(D) is the blue whale

相關試題

相關試卷

49. Among the giant ocean mammals \_\_\_\_\_, which may weigh up to 180 tons and measure 98 feet in length.
(A) the blue whale
(B) has the blue whale
(C) being the blue whale
(D) is the blue whale