Question : Ultra violet radiations of the Sun do not reach the earth because, earth's atmosphere is surrounded by:

Option 1: Carbon dioxide

Option 2: Ammonia

Option 3: Chlorine

Option 4: Ozone

Question : A person who is colourblind cannot distinguish between

Option 1: Black and yellow

Option 2: Red and green

Option 3: Yellow and white

Option 4: Green and blue

Question : A glass jar contains 6 white, 8 black, 4 red, and 3 blue marbles. If a single marble is chosen at random from the jar, what is the probability that it is black or blue?

Option 1: $\frac{8}{21}$

Option 2: $\frac{11}{21}$

Option 3: $\frac{5}{21}$

Option 4: $\frac{1}{7}$

Question : A person can jump higher on the moon's surface than on the earth because : 

Option 1: The moon's surface is rough

Option 2: the acceleration due to gravity is smaller than that on the earth

Option 3: the moon is cooler than earth

Option 4: the moon has no atmosphere

Question : Which one of the following forms of phosphorus is most reactive?

Option 1: Black phosphorus

Option 2: White phosphorus

Option 3: Violet phosphorus

Option 4: Red phosphorus