Wednesday

September 28, 2016
Total # Posts: 2,358

**physics**

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See figure...

*October 5, 2013*

**physics (it's rather urgent help is appreciated**

no

*October 5, 2013*

**physics (it's rather urgent help is appreciated**

yeah

*October 5, 2013*

**physics (it's rather urgent help is appreciated**

@ss01 for the inclined wall stone throw

*October 5, 2013*

**physics (it's rather urgent help is appreciated**

@ss01 did you manage to find the time?

*October 5, 2013*

**physics**

i can't quite get the value of t

*October 5, 2013*

**physics**

thank you so much, sorry for being rather spamy so to say

*October 5, 2013*

**physics (it's rather urgent help is appreciated**

We are standing at a distance d=15 m away from a house. The house wall is h=6 m high and the roof has an inclination angle β=30 ∘. We throw a stone with initial speed v0=20 m/s at an angle α= 35 ∘. The gravitational acceleration is g=10 m/s2. (See figure...

*October 5, 2013*

**Chemistry**

Calculate the magnitude of the cohesive energy of potassium iodide (KI). The ionic radii of K+ and I−, are 152 pm and 206 pm, respectively. Assume the Born exponent n is 10. Assume a Madelung constant of 1.7. Please report your answer in kJ/mol or how to calculate it.

*September 28, 2013*

**Chemistry**

Calculate the magnitude of the cohesive energy of potassium iodide (KI). The ionic radii of K+ and I−, are 152 pm and 206 pm, respectively. Assume the Born exponent n is 10. Assume a Madelung constant of 1.7. Please report your answer in kJ/mol or how to calculate it.

*September 28, 2013*

**Bio/Math**

A population of glasswing butterflies exhibits logistic growth. The carrying capacity of the population is 200 butterflies, and rmax, the maximum per capita growth rate, of the population is 0.10 butterflies/(butterflies*month). Calculate the maximum population growth rate for...

*September 22, 2013*

**AP Bio; PLEASE HELP!**

if a fish farmer wanted to harvest his fish so that it recovered at the maximum rate, where should the population be maintained? There is a graph number of weeks vs. numbers of fish. and A B C and D marked on the graph. How do I figure it out??

*September 22, 2013*

**Chemistry**

Finally I found it.We have to do this : wavelength=h/P P^2=2*m*E P=sqrt(2*m*E) E = joule h = Planck's constant m = kg

*September 18, 2013*

**Chemistry**

Can you write the result because i found 5.067e-7 and it's wrong.I try it many time in diffrent ways baut I finished with the some result!

*September 18, 2013*

**Chemistry**

Calculate the wavelength of a proton with energy 2.45 eV. Please some help!

*September 18, 2013*

**Classical Mechanics**

thank you it help me!

*September 18, 2013*

**Classical Mechanics**

Mary wants to throw a can straight up into the air and then hit it with a second can. She wants the collision to occur at height h=5.0 m above the throw point. In addition, she knows that she needs t1=4.0 s between successive throws. Assuming that she throws both cans with the...

*September 18, 2013*

**romanticism**

Ms. Sue is correct! Just took the quick check

*September 16, 2013*

**Chemistry**

Calculate the wavelength of a proton with energy 2.45 eV.

*September 15, 2013*

**BIOLOGY**

yes, no, yes is correct

*September 12, 2013*

**science**

Green algae grow in the fur of the South American sloth. The green algae provide camouflage for this tree-doweling mammal, and from the fur and skin of the sloth the algae obtain moisture. A moth also lives in the fur. The moth larvae provide waste material used by the algae ...

*September 11, 2013*

**Social studies**

then 4

*September 10, 2013*

**Social studies**

Which of the following "best" illustrates how a President can use the news media to reach the largest segment of the public? 1) hold a state dinner for foreign dignities 2) hold a conference Cabinet members 3) meet with head of Congressional committees 4) give speech...

*September 10, 2013*

**Social studies**

Suppose the president vetoed a bill passed by Congress. According to the information, which of the following actions by Congress would most likely ensure that the bill will become? 1) let the veto stand 2) reintroduce the same legislation 3) try to override the veto with a two...

*September 10, 2013*

**social studies**

I think it's (2). Is it correct?

*September 8, 2013*

**social studies**

A 150 years ago nearly 3/4 of the working people in this country worked on farms. By the beginning of the 1980s only 1/40 did. Clearly automation "destroyed" many farms jobs. But if technology were really eliminating work, we would expect unemployment . The reason ...

*September 8, 2013*

**social studies**

I'm kind indecisive on first question (either answer: 1 or 3)

*September 8, 2013*

**social studies**

Question 1: I have (5) Question 2: I have (c) 2>>Based on the result of the studies, what should an elementary teacher do to unsure that a child with an unusual name develops normal intellectual ability? a- Make a special effort to ignore the child b- Try to give the ...

*September 8, 2013*

**social studies**

Does having an unusual name, such as Chastity, Englebert or Moon unit, have an effect on how a child develops? The results of some previous studies agrees with the commonsense idea that such as name could cause a child to be rejected or ridiculed and thus could have a negative...

*September 8, 2013*

**social studies**

When choosing a name for a child, how could a parent best use this study to help ensure the child's normal social development? 1 keep in mind that other characteristics are more important than name 2try not to choose an ethnic name 3Consider an unusual name because it will...

*September 8, 2013*

**Quantum physics**

@ Lord The circuit is a phase change (Z) with a Hadamard (H); plug in the eqn (simple arithmetic if u understand the material) TY for ans tho, wish i knew how u arrived to it, i wrote out all the y's and i couldnt figure out s

*September 8, 2013*

**Quantum physics**

ANS TO 3 IS c WATS Q10?

*September 8, 2013*

**Quantum physics**

7)A) I,H 7)B) X,H

*September 8, 2013*

**Quantum physics**

Someone give me Q3 and I give him/her all the others questions!

*September 8, 2013*

**Quantum physics**

any1 got the ans to q 10?

*September 8, 2013*

**Quantum physics**

Hey can any1 help me with question 10, on my last try, i cant seem to figure it out

*September 7, 2013*

**Quantum physics**

Ans to q2 above, i can help with the other 2q's

*September 7, 2013*

**Math**

Find the derivative of y=sin(x)*(sinx+cosx)

*September 4, 2013*

**AP Calc**

How do you find the derivative of y=sin(x)*(sinx+cosx)

*September 4, 2013*

**AP Calc**

Find the equation of the tangent line at the indicated point. y=5th root of (3x^3+4x) at (2,2)

*September 4, 2013*

**Biology**

You are testing a hypothesis that population density of a particular plant species influences the rate at which a pathogenic fungus infects the plant. Because the fungus causes visible scars on the leaves, you can easily determine whether a plant is infected. Design an ...

*August 26, 2013*

**8th Grade Math**

cancel out the denominator by multiplying by greatest common factor so 2. 2(5/2t-t)=2(3+3/2t) so now equation is 5t-2t=6+3t then solve. 3t=6+3t you should get no solution

*August 26, 2013*

**thermodynamics**

Use the Gibbs Free Energy Equation: ^G=^H-T^S ;where ^ represents Delta. Plug in the values and you are done! Remember to convert 25C to Kelvin.

*August 25, 2013*

**physics**

Use Couloumb's law: F=q1q2/d^2 We get force is inversely proportional to the square of the distance. Solve the rest yourself.

*August 24, 2013*

**math**

Which situation can be modeled by tossing a coin three times? a. choosing which one of sixteen teams will win a tournament c. selecting a desk from thirty-six in a classroom b. deciding which English teacher of eight will win a trip to London d. picking one of six math teachers

*August 17, 2013*

**Math**

so b?

*August 17, 2013*

**Math**

cause i dont understand what you saying

*August 17, 2013*

**Math**

Just tell the answer

*August 17, 2013*

**Lab math**

You are doing a red blood count with a standard dilution of 1/200. The area counted is 10 red squares in a Neubauer chamber. Under these conditions, what is the factor that would be used to determine the number of cells in the undiluted blood?

*August 7, 2013*

**Chemistry/lab math**

Thank you very much for this further clarification; I understand what it is asking now.

*August 7, 2013*

**Chemistry/lab math**

Okay when you set up the equation likewise for potassium and solve it the same way is the answer supposed to be the same? I'm just confused as to whether the question is asking if each should be prepared differently or it's just one solution you're working with.

*August 7, 2013*

**Statistics**

Some answers are wrong.

*August 4, 2013*

**English**

What are the stories that go with each of the tools that Sanders discusses in his essay "Inheritance of Tools?" I don't really understand what the question wants, so I started by saying the history of the hammer. What can I write about the other tools?!

*July 29, 2013*

**Math**

if x and y are two different integers in S, which of the following must be the square of an integer I. (x-1)(y-1) II. 4(x-1) III. x^2+y^2 a. none b. I only c. II only d. III only e. I and II

*July 25, 2013*

**Math**

each "word" in a special code is a three digit number. if no word in the code can begin with a 1 or 0, what is the greatest number of different words the code can contain? 28 512 800 900 1000

*July 25, 2013*

**Math**

if an integer is added to its square, the units' digit of this sum could be....? 1 2 3 4 5

*July 25, 2013*

**Math**

a drugstore had a promotion in which $0.50 was refunded to customers for each $10.00 spent on merchandise. if a customer spent $20.00 on merchandise during this promotion, the refund was equal to what % of the amount spent? 1 1/4% 2 1/2% 5% 25% 50%

*July 25, 2013*

**Math**

if x is r percent of y and if k is s percent y, then x is what percent of k? 100(r+s)% 100/rs% 100r/s% 100s/r% rs/100%

*July 22, 2013*

**Math**

in a league with 6 teams each team is scheduled to play each other team exactly twice. what is the total number of games that are scheduled in the league?

*July 22, 2013*

**math**

if x,y, and z are different integers and x+y+z=3, what is the least possible value of z? -3 1 2 3 cannot be determined from information given

*July 21, 2013*

**math**

if c+4=2a+7b, what is the value of c+6 in terms of a and b? 4a+7b 2a+7b-2 2a+5b+2 2a+9b 2a+7b+2

*July 21, 2013*

**math**

thank you

*July 21, 2013*

**math**

when a large cake is cut into pieces that each weigh 3 ounces, it yields 110 pieces. how many pieces would the cake yield if it were cut into 2 ounce piece instead?

*July 21, 2013*

**math**

a total of $24.00 is to be divided among three children in amounts proportional to their ages. if the children's age are 9, 12, and 15 years, how much money will the YOUNGEST recieve? 2 3 4 5 6

*July 21, 2013*

**Math**

Jason has to sell a box of candy bars for a fundraiser. Yesterday he sold 1/3 of the total number of candy bars that came in the box, and today he sold 3 candy bars. If his sales for these two days was 11/30 of the total number of candy bars that came in the box, how many ...

*July 21, 2013*

**Stats**

A pizza parlor has 13 different toppings available for its pizzas, and 2 of these toppings are pepperoni and anchovies. If a customer picks 2 toppings at random, find the probability that pepperoni is one of the toppings. Round to four decimal places.

*July 17, 2013*

**AP Calc**

Solve the following absolute value inequalities: |x+1|<=|x-3| I promise I'm not posting my whole homework assignment. These are questions that I skipped and have no clue how to do out of a huge packet.

*July 12, 2013*

**AP Calc.**

ohmygosh.. i'm an idiot.. thank you! you're the bestt!(:

*July 12, 2013*

**AP Calc.**

How did you go from the original question to the 1st step?

*July 12, 2013*

**AP Calc.**

but don't you have to get rid of the negative exponents somehow..?

*July 12, 2013*

**AP Calc.**

I don't get it...

*July 12, 2013*

**AP Calc.**

Simplify: [(x^-3)-x]/[(x^-2)-1]

*July 12, 2013*

**AP Calculus**

Got it. Thanks lol

*July 12, 2013*

**AP Calculus**

Wait.. does it matter if it's f(x) or f(y)?

*July 12, 2013*

**AP Calculus**

okay thank youu so much. This is a summer review packet before calculus and I don't remember how to do any of this!

*July 12, 2013*

**AP Calculus**

If f(-x) = f(x), the function is even. If f(-x) = -f(x), the function is odd. If neither is true, the answer is neither.

*July 12, 2013*

**AP Calculus**

Show work to determine if the relation is even, odd, or neither. 1. 3x=|y| (|y|=abs. value of y) Simplify the following complex fractions. 2. [(3/x)-(4/y)]/[(4/x)-(3/y)] PLEASE HELP!

*July 12, 2013*

**AP Calculus**

Oops.. thankyou haha

*July 12, 2013*

**AP Calculus**

I'm suppose to simplify it, but I keep getting 3y-4x/4y-3x. Can you please show me how to do it?!

*July 12, 2013*

**AP Calculus**

[(3/x)-(4/y)]/[(4/x)-(3/y)]

*July 12, 2013*

**Science**

Female silkworm moths (Bombyx mori) attract males by emitting chemical signals that spread through the air. A male hundreds of meters away can detect these molecules and fly toward their source. The sensory organs responsible for this behavior are the comblike antennae visible...

*July 3, 2013*

**Science**

If you were a pharmaceutical researcher, why would you want to learn the three dimensional shapes of naturally occurring signaling molecules?

*July 3, 2013*

**math**

If you are trying to find the area of the triangle you could use trig to find the height of the triangle and then use the formula 1/2 base x height. So draw the Isoceles triangle with each leg 3cm and the base 4cm Draw a centre line forming two right angled triangles find the ...

*June 26, 2013*

**Science**

x-t graph is a displacement vs time graph..right? so you would have a vertical axis as you displacement (distance) and a horizontal axis as the time (in seconds). uniform acceleration means an object moves with a change in velocity that is equal in amount. velocity is a change...

*June 17, 2013*

**Change of subject formular**

in y = x-8, the subject is y. to change that is to make x the subject i.e. the equation must become x = .... here are the few rules to consider; 1. change the sign of the variable when you move it to the other side of the equation. 2. the subject must always be isolated on the...

*June 17, 2013*

**Chemistry**

that strange!! the amount of heat evolved for a particular substance is Q = mc?T where m is the mass of that substance c is the specific heat capacity and ?T is the change in temperature during transition change or reaction. So as the mass increased so the Q as well.

*June 17, 2013*

**Physics**

I think its possible. How can the toy cars are controlled with a controller? isn't that an example of electricity been carried through air? If not then am wrong.

*June 17, 2013*

**Grammar**

I'm sending an email to my teacher. and I wanna know how to send it like the correct way. Hi Miss rodriguez I wanted to know what's my score for reading they still haven't posted it on the portal

*June 11, 2013*

**Physics**

The velocity of a vehicle is uniformly reduced from 72km/h to 24km/ over a distance of 250m down a decline of 1:25 the mass of the vehicle is 1.5Mg and its tractive resistance is 400N. The retardation is uniform. Calculate the total constant braking force required so I found ...

*June 3, 2013*

**geometery**

one could say 8/3 = 12/height h(8/3) = 12 h = (12x3)/8 h = 4.5 or use trigonometry and say sinX= 3/8 X = (1/sin)3/8 X = 22.02 which is the angle of the incline so sin(22.02) = h/12 12sin(22.02) = 4.5

*June 3, 2013*

**Chemistry**

a) A pressure vessel contains a large volume of CO2 gas at 10 atm pressure. A membrane composed of a poly(ether ketone) polymer with thickness 100 microns and net effective area of 100 cm2 covers a small perforated port in the container. The solubility of CO2 in the polymer at...

*June 2, 2013*

**Chemistry**

For each pair of structures shown below, indicate whether the two species are identical molecules, enantiomers, or isomers of some other sort.

*June 2, 2013*

**Chemistry**

a) A pressure vessel contains a large volume of CO2 gas at 10 atm pressure. A membrane composed of a poly(ether ketone) polymer with thickness 100 microns and net effective area of 100 cm2 covers a small perforated port in the container. The solubility of CO2 in the polymer at...

*June 2, 2013*

**Chemistry**

At very low temperatures the carrier concentration in one of these materials appears to diminish very rapidly. Why is this? Please choose the option that BEST describes this phenomenon.

*June 1, 2013*

**Maths**

Hi I think this is how it should be done, not completely sure please check other scources as well For this question to be answered at least a basic shape is required, is it a rectangle, is it a circle. The optimisation of the perimeter of a rectangle or square could be found ...

*June 1, 2013*

**math**

the rule of fractions is when you add or subtract you need to make the denominators the same 2/3 +3/5 becomes (2x5)/(3x5)+ (3x3)/(5x3) =10/15+9/15 now add the numerators 19/15 5/6 - 3/4 =10/12-9/12 =1/12 with multiplication just multiply both top and bottom 3/5 x 2/5 = 6/25 ...

*June 1, 2013*

**chemistry**

Scratch what i just said out. also, out of the choices provided, which one is closest to 'trigonal pyramidal', because it definitely isn't trigonal planar.

*June 1, 2013*

**chemistry**

It's Tetrahedral, the others i don't know.

*June 1, 2013*

**Chemistry**

Nope. just checked. though there might be a third correct answer...

*May 31, 2013*

**chemistry**

it's wrong. why is it wrong?

*May 31, 2013*