ANSWER:A
SOLUTION :A seismograph is an instrument that measures and records the vibrations caused by earthquakes. The first seismograph was developed in 1890. Seismographs are installed around the world as part of a seismographic network.

ANSWER:A
SOLUTION:A lactometer is a small glass instrument that tests the purity of milk by measuring its density. It works on the principle of specific gravity, which states that the more water in milk, the more the lactometer will sink in it. A lactometer with more cream will float in the milk.

ANSWER:C
SOLUTION:An altimeter is an instrument used in aircraft to measure altitude, or the distance of a point above sea level. It’s a vital navigation instrument for pilots to monitor their height above the Earth’s surface.

ANSWER:A
SOLUTION:The Richter scale is used to measure the magnitude of an earthquake, which is the amount of energy released during an earthquake.

ANSWER:A
SOLUTION:A hygrometer is an instrument that measures the relative humidity of air or other gases by measuring the amount of water vapor they contain. It’s also known as a wet and dry bulb thermometer and consists of two similar mercury thermometers.

ANSWER:A
SOLUTION :Fathom is the unit of Depth. One fathom is equal to 6 feet.

ANSWER:C
SOLUTION:The Dobson unit (DU) is used to measure the thickness of the ozone layer in a column of air from the ground to the top of the atmosphere.

ANSWER:C
SOLUTION: Cusec, or cubic feet per second, is a unit of measurement for the rate of water flow, particularly through a pipeline. It is still used by the department of irrigation. One cusec is equal to 28.317 liters per second.

ANSWER:B
SOLUTION: One barrel of oil contains 159 liters. One metric ton of oil corresponds to around 7.5 barrels on average, depending on the density of the petroleum or petroleum byproduct.

ANSWER:D
SOLUTION:The SI unit of length is a meter Angstorm = 1/1010 m Millimetre = 1/103 m Fermi = 1/1015 m Hence, the smallest unit of length is fermi.