# Posts by abcd

Total # Posts: 75

**Math**

We have this at the U of A too

*February 13, 2017*

**math**

PQRS is a cyclic quadrilateral. Then find the value of x

*February 4, 2017*

**Thermodynamics**

Consider air as an ideal gas with Cp=1000 J/(kg.K), R=287 J/(kg.K) and ??1.4. It is compressed from 1 bar, 300K to 10 bar using a compressor. The compressor can be considered adiabatic but not reversible. The flow rate is 2 kg/s, and the entropy production rate is 200 W/K. 1....

*November 22, 2016*

**Thermodynamics**

Consider air as an ideal gas with Cp=1000 J/(kg.K), R=287 J/(kg.K) and Î³â‰ˆ1.4. It is compressed from 1 bar, 300K to 10 bar using a compressor. The compressor can be considered adiabatic but not reversible. The flow rate is 2 kg/s, and the entropy ...

*November 22, 2016*

**Thermodynamics**

Consider 2 kg of an ideal gas (R=300 J/(kg.K) and Cp=1000 J/(kgK)) contained in a piston cylinder arrangement. The cylinder has a small valve at the end opposite to the piston.The cylinder walls are not adiabatic and allow heat transfer. The initial pressure and volumeare 0.1 ...

*November 22, 2016*

**Thermodynamics**

plzzz give the answer onlyyyy

*November 22, 2016*

**Thermodynamics**

1.What is the entropy production rate (in kW/K)? 2.If the process is possible, what is the outlet dryness fraction? 3.if the process is possible, what is the power output of the turbine, in MW?

*November 22, 2016*

**Thermodynamics**

Consider 100 kg/s of steam expanding in a turbine. The inlet to the turbine is at 15 MPa, 500 degrees C. The steam expands to 0.01 MPa. The exit entropy is 6.200 kJ/(kg.K). Though the turbine is well insulated, at a place where the temperature is 127 degrees C, a loss of ...

*November 22, 2016*

**math**

prove that tan(π/4+x/2)+tan(π/4-x/2)=2sec x

*October 8, 2016*

**math**

idk

*August 2, 2016*

**Math**

Exactly one triangle exists with the given conditions, and it must be a scalene triangle.

*April 7, 2016*

**stats**

Assume it is known that the probability of birth is equal in all months. What is the probability that in the STAT 1025 class of 120 students, exactly 20 students have their birthdays in either August or September? Solve using (i) the exact Binomial distribution, (ii) the ...

*February 27, 2016*

**alpha**

We know sec²ø-tan²ø=1 Therefore (secø+tanø)(secø-tanø)=1 From this we get secø-tanø=1/x,secø+tanø=x Subtract both equation 2secø=x+1/x Secø=1/2(x+1/x)

*August 1, 2015*

**Math**

Cara order a veggie pizza she she ate 3 slices of the veggie pizza how many factions of the pizza are left

*August 18, 2014*

**Physics**

In a relay race the second runner does not start from rest. it covers 100 m in 10 sec, finishing with maximum velocity of 12 m/sec, assuming the constant acceleration, determine his initial velocity. ??

*April 2, 2014*

**Cyber safety**

A 1&3 B

*February 27, 2014*

**Physics**

any one Q2_2_5

*July 27, 2013*

**Maths**

Mariolys is creating a numbered list of distinct integers. Luigis sees that there are N numbers in the list, and states that he can find either a subsequence of length 13 with increasing terms or a subsequence of length 17 with decreasing terms. What is the minimum value of N ...

*May 29, 2013*

**Maths**

Points A,B,C are given on circle Γ such that AB=BC. The tangents at A and at B intersect again at point D. The line CD intersects Γ again at E. The line AE intersects BD at F. If AD=120, what is the length of FB.

*May 29, 2013*

**Maths**

Given the set of integers {1,2,3,…,801}, what is the maximum number of sets we could distribute these numbers into such that the sum of each set is exactly the same.

*May 29, 2013*

**Maths**

Let S be a set of 31 equally spaced points on a circle centered at O, and consider a uniformly random pair of distinct points A and B (A,B∈S). The probability that the perpendicular bisectors of OA and OB intersect strictly inside the circle can be expressed as m/n, ...

*May 29, 2013*

**Maths**

Find the number of pairs of non-negative integers (n,m), such that 1≤n<m≤100, n∣m2−1 and m∣n2−1. Details and assumptions The notation a∣b means a divides b, or b=ka for some integer k.

*May 29, 2013*

**Maths**

Find the denominator n of the rational number kn (k,n are both integers) such that ∣Root 2 - k/n∣ is the smallest possible, out of all rational numbers with denominator less than 1000?

*May 29, 2013*

**Maths**

Let A0=(−1,0), and let O be the origin (0,0). For each integer i≥1, we construct the point Ai so that |Ai−1Ai|=|Ai−1O| and the angle ∠OAi−1Ai is a right angle. If O,Ai−1,Ai+1 are not collinear for any value of i, what is the x-...

*May 29, 2013*

**Maths**

Let x,y,z be non-negative real numbers satisfying the condition x+y+z=1. The maximum possible value of x^3y^3+y^3z^3+z^3x^3 has the form ab where a and b are positive, coprime integers. What is the value of a+b?

*May 29, 2013*

**Maths (Geometry)**

P is a point in rectangle ABCD. The distance from P to the 4 vertices of the rectangle are 7,15,24 and N in some order. If N is an integer, determine the value of N.

*May 29, 2013*

**Physics**

That's easy. From the given conditions, height= length/2

*March 18, 2013*

**Math/Geometry**

Two circles of radius r1 and r2 are extenally tangential to each other and are also externally tangential to a staight line l. Another circle of some unknown radius is externally tangential to both the circles and to the straight line l. Find the adius of that circle.

*March 13, 2013*

**physics**

We know how to calculate the total resistance of the cylindrical conductor given its length, radius, and resistivity. But how do we calculate the equivalent resistance when the resistivity is not constant? For example, say the resistivity at a particular point at a distance x ...

*March 11, 2013*

**Geometry**

Yes, solving gives HI^2= 792.

*March 6, 2013*

**maths**

This problem is at an website (brilliant . org). Please don't answer this since the problem is open. Answer this the next week.

*February 12, 2013*

**Physics**

Two wires A and B of the same material and having same length, have their cross sectional areas in the ratio 1:6. What would be the ratio of heat produced in these wires when same voltage is applied across each?

*January 20, 2013*

**math 3rd grade**

Sarah ordered a veggie pizza she ate 3 slices of the veggie pizza how many factions of the veggie pizza are left over

*November 26, 2012*

**chemistry 101**

given the reaction: 2mg + o2-----> 2mgo . when 4.32g of oxygen react with magnesium 327kj of energy is produced. the heat of reaction for 1 mole of oxygen is???

*July 9, 2011*

**chemistry 101**

What is the coefficient for aluminum after the following equation is balanced: Al(s) + O2(g) --> Al2O3(s) options: 2 4 1 3 0

*July 8, 2011*

**chemistry 101**

so whts th answer from th options??

*July 8, 2011*

**chemistry 101**

Given the following dissolving process: Fe2(SO4)3 (s) = 2Fe3+ (aq) + 3SO42- (aq) How many grams of iron (III) ions are produced when 0.450 moles of sulfate ion are produced? options: 50.3 g 16.8 g 50.3 g 37.7 g 75.4 g

*July 8, 2011*

**chemistry 101**

Consider the following reaction. CaO (s) + CO2 (g) = CaCO3 (s) A chemist allows 14.4 g of CaO and 13.8 g of CO2 to react. When the reaction is finished, the chemist collects 19.4 g of CaCO3. Determine the limiting reactant, theoretical yield, and percent yield for the reactio ...

*July 8, 2011*

**chemistry 101**

How many grams of oxygen are in 40.1 g of calcium hydroxide? options: 17.3 g 8.64 g 20.1 g 0.541 g 11.2 g

*July 8, 2011*

**chemistry 101**

Lakes that have been acidified by acid rain can be neutralized by the addition of limestone (CaCO3). How much limestone in kilograms would be required to completely neutralize a 5.2 x 109 L lake containing 5.0 x 10-3 g of H2SO4 per liter?

*July 8, 2011*

**chemistry 101**

How many molecules of oxygen are produced from the decomposition of 8.75 g of hydrogen peroxide in the following equation Mg + H2O2 --> MgH2 + O2 options: 8.75 x 1024 6.02 x 1023 1.55 x 1022 5.27 x 1024 1.55 x 1023

*July 8, 2011*

**chemistry 101**

How many moles of oxygen are in 3.45 mol of diphosphorus pentoxide? options: 5.75 mol O 13.5 mol O 6.90 mol O 3.45 mol O 17.3 mol O

*July 8, 2011*

**chemistry 101**

Determine the empirical and molecular formula for a compound made from 54.09% calcium, 2.72% hydrogen, and 43.18% oxygen with a total molar mass of 222.3 g.

*July 8, 2011*

**chemistry 101**

Calculate the empirical formula for the following compound: potassium tartrate found in baking powder: 20.8% K, 2.7% H, 25.5% C, and 51.0% O

*July 8, 2011*

**chemistry**

Benzene, C6H6, is a known carcinogen that burns in air according to the following unbalanced equation: C6H6(l) + O2(g) CO2(g) + H2O(g) a. What is the mole ratio of O2 to C6H6? b. How many moles of O2 are required to react with each mole of C6H6? c. How many moles of ...

*July 3, 2011*

**chemistry**

Suggest chemical reactions that could be used to identify the contents of four unlabeled bottles containing solutions of the following substances: CuSO4, Al2(SO4)3, Pb(NO3)2, and FeSO4.

*July 3, 2011*

**chemistry**

Predict whether reactions should occur between aqueous solutions of the following compounds. If so, write balanced molecular and net ionic equations for the reactions. Include physical states. a. (NH4)2CO3 and CrCl3 b. Ba(OH)2 and HCl c. FeCl3 and NaOH d. Ca(HCO3)2 and HNO3

*July 3, 2011*

**chemistry**

Consider the following equations. For each, decide whether it represents a chemical reaction or a physical change. a. SnCl4(aq) + 4H2O(l) Sn(OH)4(s) + 4HCl(aq) b. 4K(s) + O2(g) 2K2O(s) c. NaCl(s) Na+(aq) + Cl-(aq)

*July 3, 2011*

**English - Shakespeare**

Thanks

*January 7, 2009*

**English - Shakespeare**

In "Othello" Desdemona is slapped by Othello in Act 4 Scene 1. Why soesn't she defend herself eventhough she's innocent? I was thinking that maybe she was just too stunned to do anything or maybe she thought that something was wrong such as he was ill or he ...

*January 7, 2009*

**math riddle**

A robber ducky

*January 5, 2009*

**math**

Thanks

*January 5, 2009*

**math**

Can anyone help, my calculator does not have enough space for simplifying this, sqrt[(16*10^113)/250*10^-28]

*January 5, 2009*

**algebra**

Just add the two together as they are then divde the term with no variable by the one with a variable to get your answer.

*January 5, 2009*

**algebra**

y=5/3X-4

*January 5, 2009*

**math**

Ah, thank you. I was thinking that 5 had to be divided into squares but it is prime.

*January 4, 2009*

**math**

It's impossible to factor x^2-6x+5 right?

*January 4, 2009*

**math**

ok thanks

*January 4, 2009*

**math**

Sorry this was meant for Reiny

*January 4, 2009*

**math**

nevermind

*January 4, 2009*

**math**

Are you sure that (2x+1)(x+3) is the factored version of 2x^2+5x+3?

*January 4, 2009*

**math**

oh that's what you mean. I guess we call it something different. Thanks

*January 4, 2009*

**math**

Not really

*January 4, 2009*

**math**

What factoring technique would be used to factor 2x^2+5x+3?

*January 4, 2009*

**religion and social studies**

I would have to say because religion has been an integral part of society since humans have lived. Social studies is studying society, people, customs, etc.

*December 30, 2008*

**jewerly marking**

I believe it is Continental silver. Yaahoo 82.5% silver and choose 3rd link

*December 30, 2008*

**algebra**

Subtract 2cm from 16cm and then divide that number by 2. After that multiply it by 5.

*December 30, 2008*

**math**

Thanks, I hope that's it.

*December 30, 2008*

**math**

Last question. If I have found all of the linear equations and have all of the intersection points for this feasible region, how do I calculate the maximum and minimum using the given function f(x,y)=-x+3y?

*December 30, 2008*

**Biology**

1.Cytosol is the liquid found within a cell, so I would say D. BUT cytoplasm is actualy the cytosol + organelles. This would make D. and E. the same so I would say A. none of these. 2.Prokaryotic cells divide by binary fission. Although this is the way bacteria divide they ...

*December 30, 2008*

**math**

Thanks, I appreciate the help.

*December 30, 2008*

**math**

Pertaining to the previous question, if two of the vertices of a feasible region are at (1,3) and (6,1) how would the linear equation representing a line connecting them be found?

*December 30, 2008*

**math**

Thanks

*December 30, 2008*

**math**

How would the maximum and minimum values of a feasible region be found with a given function such as f(x,y)=-x+3y?

*December 30, 2008*

**Drama**

What are the techniques used in improv? I am assuming that you a refering to improvisational comedy rather than music or other areas. Since this is not my area of expertise, I searched Google under the key words "improv techniques" to get these possible sources: http...

*October 10, 2006*

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