Numismatics is
Answer: A
Numismatics is the study of coins, and of currency generally - including tokens, medals and paper money.
Philately is the study of stamps and lepidopterology of butterflies.
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How are the following elements arranged in the Periodic table?
Answer: B
The first five elements of the periodic table, in order of atomic number, are H, He, Li, Be and B - hydrogen (1), helium (2), lithium (3), beryllium (4) and boron (5).
The table is arranged by atomic number, which is the number of protons in the nucleus, not by atomic mass or by any chemical property.
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Yeast is an important source of-
Answer: C
Yeast is a rich source of the B group of vitamins - thiamine, riboflavin, niacin, folate and B12 in fortified forms.
Brewer's yeast and yeast extract are used as supplements for this reason. Yeast contains no vitamin C, which comes from fresh fruit and vegetables.
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Cholera is caused by?
Answer: A
Cholera is caused by Vibrio cholerae, a comma-shaped bacterium spread through water contaminated by faeces.
Its toxin makes the intestinal cells pour out water and salts, causing the massive watery diarrhoea that can kill by dehydration within hours. John Snow traced an outbreak to a London water pump in 1854.
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Which of the following are the two main constituents of granite?
Answer: C
Granite is composed mainly of silica and alumina - that is, of quartz and feldspar, with mica in smaller amounts.
It is a coarse-grained igneous rock, crystallised slowly at depth, and its silica-rich composition is why it is classed as an acid igneous rock.
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Fathom is the unit of
Answer: B
The fathom measures depth of water. It equals 6 feet, or about 1.83 m.
Its name comes from the Old English for the span of a man's outstretched arms, which is how a sounding line was measured off by hand.
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For Galvanizing Iron which of the following Metals is used?
Answer: A
Galvanised iron is coated with zinc, usually by dipping the sheet in the molten metal.
The zinc protects in two ways: it seals the surface, and being more reactive than iron it corrodes in preference even where the coating is scratched - sacrificial protection.
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What does airbag, used for safety of car driver, contain?
Answer: B
A car airbag contains sodium azide, NaN3.
A crash sensor ignites it and it decomposes in milliseconds, releasing nitrogen gas that inflates the bag:
\[ \mathrm{2NaN_3 \rightarrow 2Na + 3N_2} \]
The whole process takes about 30 milliseconds.
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Atoms are composed of:
Answer: D
An atom consists of electrons and a nucleus. The nucleus holds the protons and neutrons and nearly all the mass; the electrons occupy the space around it.
Rutherford's gold-foil experiment showed that the positive charge and the mass are concentrated in a nucleus about 10,000 times smaller than the atom itself.
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A married couple adopted a male child. A few years later, twin boys were born to them. The blood group of the couple is AB positive and O negative. The blood group of the three sons is A positive, B positive, and O positive. The blood group of the adopted son is
Answer: A
The adopted son is the one with O positive blood.
The parents are AB and O. An AB parent passes on either A or B, and an O parent passes on O, so every biological child must be group A or group B - never O and never AB. The son with group O therefore cannot be theirs.
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