What would happen if archaebacteria would disappear

Everyone would die.

We'd immediately lose all photosynthesis and most of the energy production done by eukaryotes, since these processes are carried out by bacteria living inside eukaryotic cells (chloroplasts and mitochondria, respectively). This would be sufficient to knock out virtually all eukaryotic life. I suppose some archaea would survive and do well.

Now, maybe we should no longer count mitochondria and chloroplasts as bacteria, given that they've been living inside eukaryotic cells for several billion years. In that case, we would still be in deep trouble. We'd lose the nitrogen fixation abilities of Rhizobium, which would strongly affect agricultural production; various bacteria that help us and other animals digest food; most marine photosynthesis; and some other things.

hydrocarbons are organic compounds that contain only hydrogens and carbons. they can be saturated (those which contain only carbon-carbon single bonds) or unsaturated (those which contain carbon-carbon double or triple bonds) in nature. hydrocarbons can undergo several reactions like substitution, elimination etc.  

on substituting one or more hydrogen atoms in hydrocarbon it results in the formation of haloalkane. as the halogen atoms are large compared to the carbon and hydrogen atoms, due to which the molecular weight increases and the bond become polar because of presence electronegative halogen atom and results in the increase in boiling point of the haloalkane.

thus, the correct option is (b) that is the boiling point of the new compound increases on substituting a hydrogen atom with a halogen in a hydrocarbon.

here is table 2-2:

country

percent of eligible voters that voted

rank

united states

44.9%

138

canada

60.1%

107

costa rica

84.6%

14

hungary

66.9%

82

japan

57.0%

118

egypt

27.7%

159

south africa

85.5%

10

ans is no, the data set cannot be plotted as a single circle graph