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    Conditional Probability Help

    Please help with the following: Given: 2% professional cyclists have taken an illegal substance in the past 6 months The test only produces positive or negative results 90% cyclists that have taken an illegal substance in the past 6 months will test positive 1% cyclists who did not take any...
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    Combinations Help Urgent

    Hi, Can someone please help with this question: A small company has 55 employees: 4 senior executives, 15 managers and 36 non-executives. A group of 5 employees are chosen at random, what is the probability that there are exactly 2 senior executives in the group? Answer: 0.036 Thanks!
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    New Syllabus HSC Chemistry and Biology Notes

    Hi everyone, I graduated in 2021 with an internal rank of second for chemistry and fourth for biology (as attached). I am selling detailed study notes for both subjects: $6 per module $20 for all four modules of either biology OR chemistry (modules 5-8) $30 for full course biology AND...
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    Practice Trial HSC Questions HELP

    Hey guys, The attached are a few questions I need help with. Any help is appreciated. Thanks!
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    Motion using Vectors HELP

    A small finishing boat can travel at 8km/h in still water. It is being steered due east, but there is a current running south at 2km/h and a breeze blowing the boat south west at 4km/h. Find the resultant velocity of the boat, giving the speed correct to 2dp and the direction correct to nearest...
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    Can someone please check my working for vectors?

    Hi guys, I’m wondering if anyone could check what I’ve done wrong for part c of the attached question as I got 3/2 for both alpha and beta while the answer says 2/3. Thanks!
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    Geometrical Proofs using Vectors Questions

    Hi guys, It'll be much appreciated if anyone could me with any of the below question. Thanks to all!! Note: please prove all the below using vectors. 1. In any trapezium ABCD, show the length of MN (which connects the midpoints of the parallel sides of AB and CD) must be half the sum of AC and...
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    Vector Projections Qs Help Plz UGRENT

    1. Given a=(3,4) and b=(2,1), find the area of the triangle formed by a, b and the projection of b onto a. ANS: 1 (note: bolded letters are all vectors) 2. Given a=(3,4) and b=(2,1), find the area of the triangle formed by a, b and the projection of a onto b. ANS: 5 Can someone please explain...
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    Acid Base Reactions Help Plz

    1. Which of the following is not basic: A. SO4 2- B. NO3 - C. HPO4 2- D. NH3 2. Kb=4.3*10^-4, for the dissociation of ethylamine (C2H5NH2). Calculate Ka for its conjugate acid. 3. The solubility of CO2 is pure water at 25 degrees celsius and 0.1 atm pressure is 0.0037M. Assuming that all of...
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    Dot Products and Projections HELP PLZ

    Hi guys, I'm stuck on the following questions, please give me a hand. Note: all the letters (vectors) below are meant to have a tilde beneath it, it's just me not knowing how to type it out :( 1. If a·b=3, a·c=4, b·c=-2 and |b| =1 then evaluate (a-b)·(2b+3c) ANS: 22 2. Find the possible values...
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    Vectors Help Urgent

    Hi guys, That attached are some questions that I need help with. The answers printed in small font on the bottom right hand side of each question (the answer for the last question got cut off, it’s meant to be 1/2) Many thanks:)
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    Acid Base Reactions Help

    1. Given: OCl- + HCl <-> HOCl + OH- Which of the below will increase the concentration of HOCl? A. Adding H2O B. Adding HCl C. Adding KCl D. Adding KOH 2. Describe two properties used to distinguish between a strong monoprotic acid and a weak monoprotic acid of the same concentration (1.00 mol...
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    Acid Base Reactions Help

    Hi guys, Here are some questions that I need a hand on: 1. Which of the following can react as a B/L base when mixed with water? (A) HCO3- (B) Cl- (C) CH3COOH (D) NaNO3 2. Describe how phosphine (PH3), oxide (O2-) and the carbonate ion (CO3 2-) act as Arrhenius' bases using reaction...
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    Dilations Help

    Hi guys, I need some help on a couple of questions: 1. Find the equation if f(x)=1/3 x^3 is translated horizontally 1/2 units to the right. Why is the answer 1/2(2x-1)^3 instead of 1/3(x-1/2)^3? What are the differences? 2. f(x)=ln x has a vertical translation of 2 upwards and vertical...
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    Organic chemistry help

    Hi guys, I need a hand on these questions: 1. Draw the structural formula of the organic product formed between: a) butanoic acid and ethanamide b) butanoic acid, 2-methylpropan-1-ol and an acid catalyst 2. Write a balance chemical equation for: a) the dissociation of butanamide in water...
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    2020 Fort Street English Advanced Paper 1 Trial

    Hey guys, Does anyone have sample answers to the short answer questions to this paper? Note: the paper is attached
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    2020 Normanhurst Ext 1 Trial Paper Help

    Hi, Can I please have a hand on these two questions: Consider the polynomial P(x) = x^3+x^2+cx-10. It is known that two of its zeros are equal in magnitude but opposite in sign. What is the value of c? (a) root 10 (b) 10 (c) -10 (d) - root 10 Thanks!!
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    Dilation Help

    Hi, Can someone please explain how to dilate k(x-2)^2+c in the positive y-direction by a factor of 4. Does this mean horizontally dilating the function? Note: the answer is y=4k(x-2)^2+4c
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    Reaction Pathways HELP

    Does anyone know how to do the attached questions? Any help is appreciated. Thanks!
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    The Crucible VS Hotel Rwanda - Faith and Resilience???

    Hi guys, How is faith and resilience explored in The Crucible and Hotel Rwanda? For Hotel Rwanda, does anyone have notes on film techniques? Thanks :)
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