thermometer is to temperature as a compass is to -

Assertion (A): The earthworms reduce the fertility of the soil.

Reason (R): They make the soil soft and porous.

Assertion (A): Diamond is used for cutting the glass.

Reason (R): The refractive index of diamond is high

Assertion (A): Plants have green leaves.

Reason (R): Plants contain phycoerythrin, the green pigment.

Which of the following set of letters complete the letter series, when sequentially placed at the gaps?
a _ cdaab _ cc _ daa _ bbb _ ccddd

Raman says "Anuj's mother is the only daughter of my mother." How is Anuj related to Raman?

Looking at the portrait of a man, Mohan said, "His mother is the wife of my father's son and I have no brother and sister." at whose portrait was Mohan looking?

Pointing to an image Madhu tells Sohan, "I am the only daughter of this lady, and her son is your maternal uncle." How is the Madhu related to Sohan's father?

Pointing to a woman, a man said, "Her father is the only son of my father." How is the man related to the woman?

Pointing to a man in the photograph a woman said, "He is the son of the only son of my grandfather." How the man in the photograph is related to that woman?