61. Which gas is used for artificial ripening of green fruit ?
A. Carbon dioxide
62. Sunsets on Mars are _________?
63. BCG vaccine is used to produce immunity against___________?
A. Whooping cough
C. Virus fever
64. The Tree sends down roots from its branches to the soil is known as:___________?
65. Which of the following is used as a lubricant?
D. Iron oxide
66. The element common to all acids is:__________?
67. Carbon, Diamond and Graphite are together called:___________?
68. Most soluble in water is:__________?
C. Common salt
69. Radiations are harmful as it:___________?
A. Causes skin cancer
B. Causes anemia
C. Alters body tissue
D. is unstable
70. An active asteroid is discovered near ________ Orbit for the first time in billion years.