but how if u see isnt it steepest at B and also why do u draw tangent and also help me with w06 q21 thanks........
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no no the higher the line the steeper it is the more is the gradient
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draw a tangent just for ure own convenience so that u get the idea nothin more.
Q21) pressure of water + pressure of oil = total pressure
PHG +PHG = 17.5*10^6 (*10^6 because we want to change megametre to metre)
(1000 * (2000-x) *9.
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+ (830 * x *9.
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= 17.5*10^6
solve this equation
x= 1260.5
which is nearest to answer D