A box contains 2 white balls, 3 black balls and 4 red balls. The number of ways  threeballs be drawn from the box if at least one black ball is to be included in the draw is ______.

 

Three letters can be posted in five letterboxes in 3^5 ways.

In a steamer there are stalls for 12 animals, and there are horses, cows and calves (not less than 12 each) ready to be shipped. They can be loaded in 3^12  ways.

If some or all of n objects are taken at a time, the number of combinations
is 2^n–1.

There will be only 24 selections containing at least one red ball out of a bag containing 4 red and 5 black balls. It is being given that the balls of the same colour are identical.

A candidate is required to answer 7 questions out of 12 questions which are divided into two groups, each containing 6 questions. He is not permitted to attempt more than 5 questions from either group. He can choose the seven questions in 650 ways.

Which of the following gas has highest contribution in global warming?

1) Carbon-di-oxide

2) Chlorofluorocarbon

3) Nitro us oxide

4) Methane

Who was the father of Indian Space Programme?

1) Dr. Vikram Ambalal Sarabhai

2) Dr. Satish Dhawan

3) Dr. Homi J. Bhabha

4) Dr. Krishnaswami Kasturirangan

Which of the following is Academic Institute Satellite?

1) CARTOSAT-2B

2) KALPANA-1

3) INSAT-2E

4) SATYABAMASAT

With reference to the Deep Carbon Observatory (DCO) which of the following statements is/ are correct?

1. It is Global Research Programme to outreach role of carbon on earth.

2. It conducts field observations of deep microbial ecosystem.

Select the correct answer using the codes given below -

Codes :

1) 1 only

2) 2 only

3) Both 1 and 2

4) Neither 1 nor 2

At which of the following places is the Secretariat of the International Solar Alliance (I.S.A.) located at present?

1) Paris

2) New Delhi

3) Gurugram

4) New York