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    (Original post by joeheat)
    Any one help , question is advantages of monoculture and one is economies of scale? anyone know what that is
    economies of scale is when something is cheaper if it is mass produced due to lower production costs
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    What even is unit 4...... I hate this unit so much so boring.

    Also good luck to everyone for tomorrow
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    environmental impacts of fishing??
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    How did you guys find it?
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    Really nice paper! did the abiotic factor essay, what about you guys?
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    Did the abiotic as well. Paper was great 😁
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    I thought it was a nice paper. I had no idea about the measuring soil erosion experiment one though! There was a few 2/3 markers where I couldn't think of enough points. :/
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    Also did abiotic essay. What did you write about? I did
    Temperature -polytunnels and greenhouses so crop can always be at optimum temp
    Light- LED bulbs coloured to plants specific wavelength so they can maximize light absorption in chlorophyll so higher rate of photosynthesis- more growth
    pH - lime added, increases productivity because if pH is too low proteins in root hair cells won't absorb nutrients
    Soil nutrients- crop rotation and fertilizers
    Wind- barrier crops/trees so less damage to crops
    Co2/O2 can be controlled in greenhouses to maximize respiration and photosynthesis
    Water-irrigation if soil moisture gets too low
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    what did people get for the maths questions? i got 9 for number of species in the table, 7. something for the chi squared value and i got confused on the probability level so i put 0.025 as a guess. I got 2.5% for the percentage
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    anyone got any ideas about grade boundaries? last year it was 55/80 for an A. it must be higher this year
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    (Original post by DecantedOrange)
    Also did abiotic essay. What did you write about? I did
    Temperature -polytunnels and greenhouses so crop can always be at optimum temp
    Light- LED bulbs coloured to plants specific wavelength so they can maximize light absorption in chlorophyll so higher rate of photosynthesis- more growth
    pH - lime added, increases productivity because if pH is too low proteins in root hair cells won't absorb nutrients
    Soil nutrients- crop rotation and fertilizers
    Wind- barrier crops/trees so less damage to crops
    Co2/O2 can be controlled in greenhouses to maximize respiration and photosynthesis
    I did the same but put about irrigation to increase water and perforated pipes and drainage to reduce it. Then something about ploughing for aeration for nitrification, fertilisers and legumes for fixation.
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    (Original post by AmyT997)
    what did people get for the maths questions? i got 9 for number of species in the table, 7. something for the chi squared value and i got confused on the probability level so i put 0.025 as a guess. I got 2.5% for the percentage
    I got 9 and 7.something too

    0.025 is 99.75% i think.
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    (Original post by greencat55)
    I thought it was a nice paper. I had no idea about the measuring soil erosion experiment one though! There was a few 2/3 markers where I couldn't think of enough points. :/
    Yeah the experiment was tricky, it was a tray with soil in which you poured water on at different angles and measured soil loss
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    (Original post by AmyT997)
    what did people get for the maths questions? i got 9 for number of species in the table, 7. something for the chi squared value and i got confused on the probability level so i put 0.025 as a guess. I got 2.5% for the percentage
    I got 21 in the table and 7.34 for chi squared and put 2.5% for the next one. im pretty sure the table one is 21 because it was (O-E)^2/E so O = /2.4x15 +15
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    (Original post by DecantedOrange)
    Yeah the experiment was tricky, it was a tray with soil in which you poured water on at different angles and measured soil loss
    oh I got that wrong then :/ I talked about a transect down a slope and coring samples and measuring thickness of top soil :P
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    (Original post by greencat55)
    I got 21 in the table and 7.34 for chi squared and put 2.5% for the next one. im pretty sure the table one is 21 because it was (O-E)^2/E so O = /2.4x15 +15
    Yeah we debated about this in class after, both 9 and 21 work.
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    (Original post by DecantedOrange)
    I got 9 and 7.something too

    0.025 is 99.75% i think.
    wasn't it asking for what percentage due to chance? not what percentage means the trend is correct.
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    (Original post by greencat55)
    oh I got that wrong then :/ I talked about a transect down a slope and coring samples and measuring thickness of top soil :P
    There will be other methods, yours will still be right as there has been a past question almost exactly the same, both methods were on it
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    (Original post by DecantedOrange)
    I got 9 and 7.something too

    0.025 is 99.75% i think.
    It was percentage they were due to chance not percentage they were significantly different so it should be a low value i think
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    (Original post by AmyT997)
    There will be other methods, yours will still be right as there has been a past question almost exactly the same, both methods were on it
    oh good! thanks, that's good to know I haven't lost 5 marks
 
 
 
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