From an aeroplane vertically over a straight horizontal road, the angle of depression of two consecutive kilometre-stones on the opposite sides of the aeroplane are observed to be $\mathrm{\alpha } \text{and} \mathrm{\beta }$. The height of the aeroplane above the road is _____.

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence .

P: he 

Q: almost

R: planned the entire strategy of operation

S: single-handed. 

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

P: It is a fact that rice is one of the most prolific 

Q: than almost any other crop 

R: yielding a greater return per acre  

S: food crops. 

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

P: up to the end of eighteenth century, not only because it was often fatal,

Q: small pox was particularly dreaded disease,

R: but also because those who recovered

S: were permanently disfigured

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence .

P: a person bitten by a rabid dog. 

Q: would be seized by violent symptoms.   

R: after an incubation period of a month or two 

S: and die an agonizing death

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

The traveller

P: sat down 

Q: to rest  

R: by the roadside  

S: being weary,

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

P: the house was  

Q: away  

R: with its liveliest member 

S: gloomy

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

P: he was tiny man  

Q: with a sprightly walk  

R: tall  

S: barely five feet

Below is a sentence of which some parts have been jumbled up. You are required to rearrange these parts which are labelled P, Q, R, and S to produce the correct sentence. Choose the correct sequence.

P: rules and regulations 

Q; he cheerfully ignored its demands 

R: a life of   

S: unaccustomed to