(5ai)
(i)each time zone differ by 15degree in longitude
(ii)the reference point is the G.M.T
(iii)it divided within 24 time zone
(iv)it maintain the eential time for time zone in which they are
(5aii)
(i)data change by 24hours when it is crossed
(ii)the 180degree meridian represent for the original of a date line
(iii)travelers going to the east gains one day which does going to the west losses one day
(iv)it is not a straight line
(5b)
Time difference =1800 – 900
=900hrs
=9hours
Longitude = 9*15=135degree
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(8a)
Food chain can be defined as series of network in an ecosystem. It shows how the organisms are related with each other by the food they eat.
(8b)
Energy flow within a terrestrial ecosystem:
Energy from the sun is received by the producer which are plants, produce their food and hence when consumed by the consumer energy is passed, when the consumer which are animals feed on the plant, they absorb energy, use some for body development and when consumed by a higher animal, the energy is also utilised and finally when the organism dies, decomposers act on the organism and in which some energy is used and stored. Energy generally reduces down the food chain.
(8c)
(i) Plants absorb nutrients from the soil into their roots.
(ii) Animals get nitrogen from plant consumed.
(iii) Ammonication which is part of decaying process.
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(4a)
A lake is a land-locked body of slow-flowing water
(4b)
WIND EROSION LAKES: These are lakes formed where wind deflation erode and result into formation of depression in desert. If such depressions are small and shallow pan lakes may form. But sometimes such depression goes deeper to expose water table and result into formation of Oasis lakes like in Qattara Depression in Egypt.
(4c)
(i) It provides water and food for human use
(ii) It helps in water pollination purification to support ecosystems
(iii) Serves as tourist center
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