Question

19. To which of the following the oldest fossil belong
(a) Sulphur bacteria
(b) Fungi
(C) Blue-green algae
(d) Green alga
20. The atmosphere of early earth consisted largely of:
(a) water vapour (b) carbon dioxide (c) helium
21. Evidence in favour of evolution can be obtained from :
(a) morphology and comparative anatomy
(b) embryology and palaeontology
(c) taxonomy and biochemistry
(d) all of these​

Answer 1

Answer:

19.c) Blue -green algae..

20.c) helium..

21.d) all of these..

Explanation:

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