Exams

Acid which is present in vinegar is approximately 5 % of acetic acid. This can be confirmed by testing the vinegar with magnesium which gives out hydrogen as a gas.

Let the speed of the trains be x and y respectively
length of train1 = 47x
length of train2 = 31y
Relative speed= x + y
Time taken to cross each other = 33 s
=> 47x+31yx+y= 33
=> (47x + 31 y) = 33(x + y)
=> 14x = 2y
=> x/y = 2/14 = 1/7

 = 1:7

Caverns are openings in the ground. Some famous caverns in the United States are Mammoth Cave, Carlsbad Caverns, Wind Cave, and Luray Caverns.

When rainwater trickles down through the soil, it carries carbon dioxide from the air with it. This turns acidic as it moves through the soil, joining with carbon from decaying plants. This acidic rainwater then eats away at, or erodes, the rock under the ground, forming a cave or cavern. For this process to occur, the rock must be the right type; limestone, dolomite, and gypsum are common.

Passive Voice : Has the work been completed by him?

Rules in changing from Active voice to Passive voice :

1. Identify the subject, the verb and the object: S+V+O

2. Change the object into subject

3. Put the suitable helping verb or auxiliary verb

4. Change the verb into past participle of the verb

5. Add the preposition "by"

6. Change the subject into object.

Given the company has 8 SD + 6 SRP + 7 IN = 21 cars + 'x' small cars.
Given SD makes 1/4 th of the total fleet.
=> 8 = 1/4 (21 + x)
=> 32 = 21 + x
=> x = 11
Therefore, the company has 11 small cars.

RADAR - RAdio Detection And Ranging.

A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, a transmitting antenna, a receiving antenna (often the same antenna is used for transmitting and receiving) and a receiver and processor to determine properties of the objects. 

Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. It can be used to detect aircraft, ships, spacecraft, guided missiles, motor vehicles, weather formations, and terrain.

Radio waves from the transmitter reflect off the object and return to the receiver, giving information about the object's location and speed.

Ram Nath Kovind, the present President of India is from BJP, Bharatiya Janata Party.

The president of the Republic India is the head of state of India. He is also the commander-in-chief of Indian Armed Forces. He is indirectly elected by the people through members of both houses of the parliament of India, legislative assemblies of all the states of India, the legislative assembly of the Union