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The ice cover of Alaska Bay adjoining th...

The ice cover of Alaska Bay adjoining the North Pole has reduced by 40% in last-

A

10 years

B

30 years

C

20 years

D

40 years

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Assume that the chances of a patient having a heart attack is 40%. It is also assumed that a meditation and yoga course reduce the risk of heart attack by 30% and prescription of certain drug reduces its chances by 25%. At a time a patient can choose any one of the two options with equal probabilities. It is given that after going through one of the two options the patient selected at random suffers a heart attack. Find the probability that the patient followed a course of meditation and yoga?

A company has two plants to manufacture bicycles. The first plant manufactures 60% of the bicycles and the second plant 40% . Also 80% of the bicycles are rated of standard quality at the first plant and 90% of standard quality at the second plant. A cycle is picked up at random and found to be of standard quality. Find the probability that it comes from the second plant.

If one of tow identical slits producing interference in Young's expeiment is covered with glass, so that the light intensity passing through it is reduced to 50% , find the ratio of the maximum and minimum intensity of the fringe in the interence pattern.

the angle of elevation is reduced from 60^@ to 30^@ and hence the shadow of a pole is increased by 40 meter. Find the height of the pole.

A factory has two machines A and B. Past record shows that machine A produced 60% of the items of output and machine B produced 40% of the items. Further, 2% of the items produced by machine A and 1% produced by machine B were defective. All the items are put into one stockpile and then one item is chosen at random from this and is found to be defective. What is the probability that it was produced by machine B?

The probabilities that a student passes in Mathematics,Physics and Chemistry are m, p and c, respectively. Of these subjects, the student has a 75% chance of passing in at least one, a 50% chance of passing in at least two and a 40% chance of passing in exactly two. Which of the following relations are true? (a) p+m+c=19/20 (b) p+m+c=27/20 (c) p m c=1/10 (d) p m c=1/4

A radioactive isotope has a half-life of T years. How long will it take for the activity to reduce to 3.125% of its original value?

This question has Statement I and Statement II. Of the four choice given after the Statement, choice the one that best describes the two Statements. Statement -I : Holes in ozone layer are observed at the north and the south poles by scientists Statement - II : Uv radiation damage eyes causing cataract of eyes

JNAN PUBLICATION-Crisis of Environment, Plants and Animals -Example
  1. Reserpine is received from-

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  2. The habitat of grass, moss, water-lily is-

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  3. The ice cover of Alaska Bay adjoining the North Pole has reduced by 40...

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  4. The average temperature of earth had increased by 1^@C in last-

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  5. More than 99% of the glaciers are present in-

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  6. is an atmospheric condition which changes every day, every hour even i...

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  7. is the average of weather of a particular area for a long period (year...

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  8. Climate changes have an important corelation with.

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  9. CO2 is one of the important gases produced byactivities.

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  10. The biggest souce of fresh water on the earth is.

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  11. More than 99% of the glaciers are present in-

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  12. is an example of marine invertebrate animal.

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  13. The biodiversity of our country is so rich that India is termed as aNa...

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  14. We get Quinine from.

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  15. Rauwalfia medicine is derived from.

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  16. State whether True or False: Climate is the average for small period o...

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  17. State whether True or False: Hilsa fish lay eggs in the rainy season.

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  18. State whether True or False: Climate changes does not have any relatio...

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  19. State whether True or False: Some glaciers are also found in Himalayas...

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  20. State whether True or False: Sea level may fall due to the melting of ...

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