# Posts by Erin

Total # Posts: 697

**Math**

Can you please help me explain why a perfect square cannot be a prime #? Thanks!

**physics**

During a particular thunderstorm, the electric potential difference between a cloud and the ground is Vcloud - Vground = 4.3 108 V, with the cloud being at the higher potential. What is the change in an electron's electric potential energy when the electron moves from the ...

**Calculus**

Find the number c that satisfies the conclusion of the Mean Value Theorem. f(x) = x/(x + 4) [1, 8]

**Chemistry**

please help me, Aris closes in 35 minutes. it's urgent!

**Chemistry**

An alpha particle (mass 6.6 x 10^-24 grams) emitted by radium travels at 3.4 x 10^7 plus or minus 0.1 x 10^7 mi/h. (a) What is its de Broglie wavelength (in meters)? (b) Whats uncertainty in its position? for part (a) I got 1.53 meters which said it was wrong on Aris and I got...

**Math**

How would I write this out? The high temp for a day is 6 degrees C. The mean temp for the day, which is the mean of the high and low temps, is -4 degrees C. What is the low temp for the day? Thank you.

**physics**

tanTheta = h/b => b=h/tanTheta =>b= 34ft/tan(17) =>b= 111.2ft 111.2ft

**Calculus**

Find the derivative of y=xsin(2/x)? On web-assign everything that I have tried has been wrong.

**Physics**

When an air capacitor with a capacitance of 300 nF (1 {\rm nF} = 10^{-9}\;{\rm F}) is connected to a power supply, the energy stored in the capacitor is 1.95×10−5 J. While the capacitor is kept connected to the power supply, a slab of dielectric is inserted that ...

**english**

what is needed to combine two sentences with a comma

**geometry**

how do you find the height of an isosceles triangle only knowing the lengths of all three bases? EX: There's isosceles triangle ABC with vertex angle B. AB= 5x-28. BC= 2x+11. AC= x+5

**geometry**

In geometry, can a counterexample be used to determine if a conjecture is false or not?

**Physics - fluids**

A solid cylinder (radius = 0.170 m, height = 0.150 m) has a mass of 7.00 kg. This cylinder is floating in water. Then oil (ñ = 0.866 kg/m3) is poured on top of the water until the situation shown in the drawing results. How much of the height of the cylinder is in the ...

**geography**

I can't find any of the answers in the book, could you please help? 1. The landform occupying the center of the triangle that forms the indian subcontinent is the.. A Deccan Plateau B Western Ghats C Indo- Cangetic Plain D Eastern Ghats 2. Which account of an Azerbaijani ...

**Algebra**

I'm not sure how to factor 3x^3-12x^2+3x. I tried separatring the 3x so that 3x(x+1)(x-4, but I got -3x^3+-12x^2-3x^2+12x. Can you show me where I went wrong and how to properly factor this? Is there a general rule or tip for this sort of factoring with a number to the ...

**Algebra**

Is a function with a fraction (1/4) an even or an odd function? Or can fractions be neither even or odd? I have to declare one or the other, so I'm not sure what to say.

**Algebra**

I have to find the standard form of a quadratic function with the vertex of -1,4 and x intercepts of -3,0 and 1,0. What do I do when I have two x intercepts like this?

**Math for educators**

I was wondering what sort of teacher you are studying to be. I can't help you with this, but I was curious as to what subject area you are trying to get your certification in.

**Algebra**

How come there are no x intercepts for x^2-x+(5/4)? Can you show me why, please?

**Algebra**

When using -b/2a with functions, should I ignore the negative, figure out b/2a and then put a negative around it? Or should I turn 2a into -2a? Or should I go -b/-2(-a)? Thanks for clearing this up!!!

**Algebra**

It's just the number of the problem.

**Algebra**

27-f(x)=1/4x^2-2x-12. Can you show me how to find the vertex and x intercepts, step-by-step? I tried to put it in standard form, with (1/2x-1)^2-13, but my book said that's not the answer. Thanks!

**Algebra**

Where did the 1 come from in the standard form come from? How did the 5/4 become 1 when it was transferred to outside of the parentheses?

**Algebra**

I have to find the vertex, axis of symmetry, and x intercepts of x^2-x+(5/4). I put it in standard form as -(x+-.5)^2+1.5. Thus, the vertex would be .5, 1.5. But the book's answer is 1/2, 1. How did they get this?

**Algebra**

17-Identify the vertex, axis of symmetry and x-intercept(s) of F(x)=(x+5)^2-6. I have no idea how the x intercepts are -5 +/- sq. root 6 and 0. can you show me how this came to be? I factored it so it would be x^2+10x+19, but there's no common factors in ten and 19. Can ...

**History**

I tried googling this, but I couldn't find it. What is the name of the journalist (who was either British or American...I can't remember) who snuck into Saudi Arabia in the early twentieth century and disguised himself as a Muslim since no non-Muslims were allowed in ...

**Geometry**

If a/4=b/7, then a/b=?

**7th grade**

Its Oh Lay

**Chem - Stoichiometry**

How many grams of sodium carbonate is required for a complete reaction with 1.00g of calcium chloride dihydrate? Help!

**Chem - Stoichiometry**

How many grams of sodium carbonate is required for a complete reaction with 1.00g of calcium chloride dihydrate? Help!

**UNE**

I know...I realized that right after I accidentally posted - that is why there is the CORRECT post and subject right after this one called Stoichiometry. THANKS FOR THE HEADS UP, THOUGH.

**UNE**

How many grams of sodium carbonate is required to have a complete reaction with 1.00g of calcium chloride dihydrate? I can't figure this out...help!

**Physics**

1.66 m/s^2! Thanks

**Physics**

Liz rushes down onto a subway platform to find her train already departing. She stops and watches the cars go by. Each car is 8.60 m long. The first moves past her in 1.75 s and the second in 1.17 s. Find the constant acceleration of the train. I know how to find average ...

**Physics**

A motorist travels at a constant speed of 34.0 m/s through a school zone; exceeding the posted speed limit. A policeman, waits 7.0 s before giving chase at an acceleration of 3.9 m/s2. (a) Find the time required to catch the car, from the instant the car passes the policeman...

**biology**

it is everything that occupies a place in the space

**Social Studies**

how did geography affect the development of African kingdomes?

**Physics**

5.03 m/s^2

**Physics**

14.84 m/s^2

**biology**

mitochondria-hydraulic dam ribosomes-small shops nucleus-town hall endoplasmic reticulum-special carts golgi apparatus- post office protein-widget cell membrane-fence lysosomes-scrap yard nucleolus-carpenter's union

**Math- calculus**

Given f(x) = x ^ 3 - x ^ 2 -4x +4 Find the zeros of f. Write an equation of the line tangent to the graph of f at x = -1 The point (a,b) is on the graph of f and the line tangent to the graph at (a,b) passes through the point (0,-8) which is not of the graph of f. Find a and b...

**college physics**

Two small spheres, each with mass m=3g and charge q, are suspended from a point by threads of length L=0.22m. What is the charge on each sphere if the threads make an angle theta of 15 degrees with the vertical?

**college physics**

There are four charges, each with a magnitude of 2.0uC. Two are postive and two are negative. The charges are fixed to the corners of a 3.0m square, one to each corner, in such a way that the net force on any charge is directed toward the center of the square. Find the ...

**college physics**

Two small spheres, each with mass m=3g and charge q, are suspended from a point by threads of length L=0.22m. What is the charge on each sphere if the threads make an angle theta of 15 degrees with the vertical?

**Math**

Guess my rule? Write a funtion for the function. Input 6 7 8 9 Output 5 5.5 6 6.5

**Global**

Explain how the African European and the Native American cultures blended to form a latin american culture?

**English**

I am having trouble writing a topical outline and expanding it to a sentence for this paper: Marie Curie is best known as the discoverer of the radioactive elements polonium and radium, and is the first person to earn the honor of two Nobel prizes. Her work not only influenced...

**Math**

Thank you Ms. Sue!

**Math**

Your not dividing IN half, but BY half. I did it the way of using fractions. Because half is .5 or 1/2. I have no idea how he got 12 either!

**Math**

Divide 30 by half and add 10. What do you get? I think it is 70, but my friend disagrees. He thinks it's 12.

**math**

But how did you figure it out like that.

**math**

There is a circle that is cut in three slices one slice is (in fractions) 1/3 and one slice is 1/5. What fraction is the other slice. (it is a whole circle.) Can you please tell me how to I can figure this out on my own.

**Pre Algebra**

(h4) 4 (-6x7) (-9x12) the answer is -63x 19

**Reading**

Jake was new to Fair Ridge Elementary, and he was big. Jake bullied Tommy when his jeans jacket was too small for him. It stretched tight across his back and the sleeves were too short for his arms. And, Jake is taking his things from the other students. But now Jake and Tommy...

**Reading**

Secret Pal Surprises Characters and Setting? It is for my book report. Please tell me the characters (behavioral description) and where's the setting.

**Eng 102**

How can I support my thesis with compelling arguments and counterarguments? Here is my thesis statement? Although many coal industries argue that mountaintop removal coal mining is more cost effective than underground coal mining, MTR is destroying the beautiful mountains and ...

**Algebra**

y3-2y2- + 3y-4 for y+5 (-9) (-9) (-9) m.m.m 7.a.a.b.b.b

**9th grade Pre Algebra**

y3-2y2- + 3y-4 for y+5

**9th grade Pre Algebra**

I need help with exponents -n6 for n=2

**9th Pre Algebra**

I need help with exponents -n6 for n=2

**Reading**

How many hours 150 minutes for reading log? for times with reading log

**math**

thank you!

**math**

You must be at least 48 inches tall to ride an amusement park ride, and your little sister is 30 inches tall. How many inches/must she grow before she may ride the ride? You need no more than 3,000 calories in a day. You consumed 840 calories at breakfast and 1,150 calories at...

**Wilders Preparatory**

What are the modifiers for the word flexible?

**biology repost**

Predict what would happen to a red blood cell placed in each of the following external solutions. Would it shrink, swell, or not change its volume? Explain each answer in ONE sentence. a. 150 mM NaCl b. 100 mM NaCl plus 50 mM albumin

**biology**

Predict what would happen to a red blood cell placed in each of the following external solutions. Would it shrink, swell, or not change its volume? Explain each answer in ONE sentence. a. 150 mM NaCl b. 100 mM NaCl plus 50 mM albumin

**biology**

Predict what would happen to a red blood cell placed in each of the following external solutions. Would it shrink, swell, or not change its volume? Explain each answer in ONE sentence. a. 150 mM NaCl b. 100 mM NaCl plus 50 mM albumin

**Writing**

no.

**Writing**

Do you have any connections with the myth you chose? Lack of connectionss? Discuss (write) about your connections.

**Writing**

Myth Literature Response Questions about Pandora's Box? I need help?!? What happended in the story? (Write is the plot?) Write a summary with rising action, climax and resolution.

**Writing**

Myth Literature Response Questions about Pandora's Box? I need help?!?

**chem post**

what are the point groups for mer- Co Cl3 (CO3) and fac- Co Cl3 (CO3)

**chemistry**

what are the point groups for mer- Co Cl3 (CO3) and fac- Co Cl3 (CO3)

**chem**

what are the point groups for mer- Co Cl3 (CO3) and fac- Co Cl3 (CO3)

**Math**

are you good with times? I am struggling with studying with times so help me: The first walker to finish the 12 miles crossed the finish line 3 hours after the offical starting time of 10:00 a.m. At what time did the first walker finish? The judges left the finish line at 5:30...

**chemistry**

what are the symmetry elements for: cis-CoCl2(NH3)4 and trans-CoCl2(NH3)4 would it be C2 S2?

**Choosing High School Courses**

Good choice is to choose high school easy: Algebra 1, PE, and home ec (cooking class) or etc.... English is the best for writing strategy, and reading is kind of good.

**chem please**

yes. the solubility of KNO3(s) at 0.0 degree celsius is 15g KNO3/100g H2O. Also, A 320g sample of a saturated solution of KNO3(s) in water is prepared at 25.0 degree celsius (this is part of the info given). i don't know how to solve this.

**chem please**

If 60 g water is evaporated from the solution at the same time as the temperature is reduced from 25.0 to 0.0 degree celsius, what mass of KNO3(s) will recrystallize?

**chemistry: again**

What is the predominant type of intermolecular force in I2 (iodine)?

**Chemistry: help please**

What is the millimolar solubility of oxygen gas,O2, in water at 20 degree celsius, if the pressure of oxygen is 1.00atm?

**science please!**

Estimate the value of the cell potential for the following rxn: Mn02(s) + 4H30+(pH=3.8) + 2Ag(s) --> Mn2+(aq, .1M) + 6H20(l) I got Ecell=.48V delta G circle= -92640 J/mol and delta g = -107484 is this correct?

**science**

how does the life cycle of hatena compare to the origin of eukaryotic cells as noted in Margulis’ Endosymbiotic Theory? something about how one life form engulfs another and incorporates it, evolving until it becomes dependent on it and has created an entirely new life ...

**biology**

how does the life cycle of hatena compare to the origin of eukaryotic cells as noted in Margulis’ Endosymbiotic Theory? something about how one life form engulfs another and incorporates it, evolving until it becomes dependent on it and has created an entirely new life form?

**bio**

how does the life cycle of hatena compare to the origin of eukaryotic cells as noted in Margulis’ Endosymbiotic Theory? something about how one life form engulfs another and incorporates it, evolving until it becomes dependent on it and has created an entirely new life ...

**chemistry**

an electrochemical cell uses Al and Al+3 in one compartment and Ag and Ag+ in the other write a balanced equation for the rxn that will occur spontaneously in this cell would that just be Al + Al+3 + 2e --> Ag + Ag+ ?

**Algebra II- please help!**

Thank you, Reiny. My teacher taught me something very similar to your method and now I understand it. Thank you for your help! : )

**Algebra II- please help!**

Thank you so much, Damon! You really helped me out! : )

**Algebra II- please help!**

I just cannot seem to be able to grasp the concept of solving polynomial inequalities. Can someone please explain, step by step, how to solve them? Here's a problem I can't solve. Please use this as an example: (x-2)(x-5)<0 I cannot thank you enough for helping me ...

**biology**

what are the three parts of the cell theory?

**science**

what are the four properties that can be used to classify elements?

**algebra 2**

how do you solve this? -2square root7-4square root7

**history HHHEEELLLPPP!!!**

What is the society and environment of the coastal plains?

**chemistry**

what is a summary of observed behavior? maybe im thinking about it too much and its simple but im lost! HELP

**history**

Why did the cowboys go west?

**history HHHEEELLLPPP!!!**

did the railroad workers go west for job opportunities and technological advances?

**history**

they went west for job opportunities and for technological advances?

**history**

what are two reasoms why the railroad workers went west?

**history HHHEEELLLPPP!!!**

thankyou

**history HHHEEELLLPPP!!!**

Why did the miners move west? 2 reasons