# Posts by Annonymous

Total # Posts: 153

chemestry
balance equation for sodium sulfate + hydrochloric acid = sodium chloride + water +Sulfur dioxide ?

Science

statistics
construct a probability distribution for18 boys and 24 girls

math
What is the coefficient of x in (x^4 + x^3 + x^2 + x + 1)^4?

Math
What is the shortest distance between the circles defined by x^2-10x +y^2-4y-7=0 and x^2+14x +y^2+6y+49=0?

Math
Thank you Reiny for helping! I understand the problem now! :)

Math
Let f(x) = (3x - 7)/(x + 1. Find the inverse f^-1(x). Once again, thank you so much for helping me!

Math
Suppose a(x) = 3x - 7 and b(x) = 2 - x^3. Find a(b(3)) - b(a(3)). Thank you for helping me!

Algebra
Let f(x) = x^2 - 2x. Find all real numbers x such that f(x) = f(f(x)). Thanks.

Astronomy
What percentage of the stars surveyed show evidence of planets? (a) About 50% (b) About 30% (c) Less than 5% (d) Less than 1% I posted this earlier but there was not no response. I think the answer should be 40% but there is no option for that.

Astronomy
My estimate using wobble, dimming and shifting came out to be 40%, but the answer does not have it. Any suggestions?

Astronomy
What percentage of the star's surveyed show evidence of planets? (a) About 50% (b) Less than 5% (c) About 30% (d) Less than 1%

Astronomy
Thanks a lot!

Astronomy
Newton’s version of Kepler’s third law is P^2 = 4pi^2/(G(M_1+M_2)) a^3. Since the square of the period P varies inversely with the sum of the masses (M_1 + M_2), the period itself depends on the inverse square root of the object masses. If a solar system has a star ...

Astronomy
I know the answer and I don't want it, but just give me the explanation.

Astronomy
What would be the approximate power-law slope of the 2-point correlation function if all galaxies were situated on thin filaments? (acceptable range of answers is +- 10% of the correct solution).

Calculus
A particle moves along the graph of the function y= 8/3x^(3/2) at the constant rate of 3 units per minute. The particle starts at the point where x = 1 and travels in the direction of increasing x. After one hour, what is the x-value, rounded to the nearest hundredth, of the ...

Math
100

Math
A rectangular garden covers 16,000 ft2. Its length is 60 ft longer than its width. What is the width of the garden?

algebra
180

algebra
Point D(-3,5) is a vertex of triangle DEF. After rotation of the triangle about the origin D us located at (3,5). Which of the following was the rotation of the triangle? A. 90* (degrees) clockwise B. 90* Counterclockwise C. 180* D. 360*

algebra
1 3 4 are the answers

algebra
i was thinking all of them

algebra
which of the following are necessary to describe a rotation of a figure on a coordinate plane? choose all that apply the center of rotation the shape of the figure the number of degrees of the rotation the direction of the rotation

physics
The chimney of a stationary toy train consists of a vertical spring gun that shoots steel balls a meter or so straight into the air – so straight that the ball always falls back into the chimney. If the train is moving, under which condition will the ball fall back into ...

physics
The chimney of a stationary toy train consists of a vertical spring gun that shoots steel balls a meter or so straight into the air – so straight that the ball always falls back into the chimney. If the train is moving, under which condition will the ball fall back into ...

physics
A car of mass 1000 kg is on an icy driveway inclined at an angle of 33◦. The acceleration of gravity is 9.8 m/s^2 θ If the incline is frictionless, what is the acceleration of the car?

MATH
Susan spent 2/3 of her money on a shirt. If she has \$12.25 left, how much did the shirt cost?

Math
A 27 3/4 foot piece of rope will be cut into as many 2 1/2 foot pieces as possible. How many 2 1/2 foot pieces will there be and how much rope is left.

Math
You do 12 divided by 4 because you get 2 free erasers with each packet.

Criminal Justice/White Collar Crime
I think it`s D

MATH
Do you convert 16 3/4 to find out how many 1/4 pounds of hamburger you can make out of that?

Math
Thank you

Math
If Sally has \$48 in her wallet and she spends \$16 on a shirt. What fraction of the money did she spend on the shirt?

math
How do you multiply 16 3/4

math
Mike has 16 3/4 pounds of hamburger. How many 1/4 pound of burgers can he make.

math
\$59.00 divided by 0.6

Math
Or you can take 9/1-12/5

Language Arts
b,c,a,d trust me the answer are right

civics

English
Begin the introduction about your topic, then within your paragraph tell what your going to include in the others. The first sentence should tell what your doing with some kind of excitement that will make the reader want to read more.

English
I'm writing an essay about poetry. My thesis is how literal language used in poetry create more still and concrete image, while poetry that uses figurative language proves more feeling. I just have no idea how to start my introductory paragraph. What do I first say in the ...

perpendicular vectors
Find two unit vectors each of which is perpendicular to vectors (1, 1, 0) and (1,0,1) What I did: a x b = (1, -1, -1) |axb|=square toot 3 correct answer is +/- (1/√3 - 1/√3 - 1/√3) or =+/- 1/√3 (1, -1, -1)

Cross Product of Vectors
Find a unit vector perpendicular to a=(4,-3,1) and b=(2,3,-1) What I did: a x b = ((-3)(-1)-(3)(1), (1)(2)-(-1)(4), (4)(3) - (2)(-3)) =(0,6,18) Answer is (0, 1/square root 10, 3/square root 10)

Vectprs and Scalars
Why are some of these scalars and others are vectors? What's the difference and how can you tell? 1. a dot (b x c) 2. (a dot b) x (b dot c) 3. (a + b) dot c 4. a x (b dot c) 5. (a x b) dot (b x c) 6. (a + b) x c 7. a dot (b dot c) 8. (a x b) + (b x c) 9. (a x b) - c 10. a ...

Vectors/Scalars?
is (u dot v)dot (a dot c) a scalar quantity or vector quantity? What's the difference? (I'm thinking scalar since it has no direction and it only has magnitude.)

Vectors and Math
Find x, y, and z if 2(x,-1,4)-3(-4,y,6)-1/2(4,-2,z)=(0,0,0) What I did: (2x,-2,8)-(-12,3y,18)-(2,-1,1/2z)=(0,0,0) (2x-14,-1-3y,-10-1/2z)=(0,0,0) Textbook answer is -5, -1/3, -20

dot product of vecotrs
Question: Find (3a+b)dot(2b-4a) if a=-i-3j+k and b=2i+4j-5k I did: =3(-1,-3,1)+(2,4,-5)dot 2(2,4,-5)-4(-1,-3,1) =(-3,-9,3)+(2,4,-5)dot(4,8,-10)-(4+12,-4) =(-1,-5,-2)dot(0,-4,-6) =(0,20,12) =0+20+12 =32 The text book answer is -80. What did I do wrong/

Math: Intro to Vectors
but the left side has a negative sign in between the x and y, and if you multiply it by -2, it makes the x negative.

Math: Intro to Vectors
Left side = right side check type of question. x - (x + y)/2 = (x - y)/2 What I did was times the x in the left side by 2. I got: =(2x-x+y)/2 which equals =(x+y)/2 But the left side is (x-y)/2. What am I doing wrong?

Vectors
if a=3x+2y and b=5x-4y, find x and y in terms of a and b What I did: 2a=6x+4y +b=5x-4y --------- 2a+b=x 2(3x+2y)+(5x-4y)=x 6x+4y+5x-4y=x 11x=x 11x dvided by x = 11 ...that isn't the correct answer. The correct answer (according to text book) is x=2/11a+1/11b y=5/22a-3/22b ...

Chemistry
Calculate the normal boiling point of a compound that has a vapor pressure of 19.30kPa at 167 Fahrenheit and a vapor pressure of 1.86kPa at 77 Fahrenheit.

Math
(2/3)y= 15-6 (2/3)y=9 2y=3(9) 2y=27 y=27/2 y=13.5 To Check: Plug y back into equation (2/3)(13.5) +6=15

biology/cells
Plant, animal, bacteria and protist cells all can use sugar to make energy Plant cells and bacterial cells can use photosynthesis and animal cells do cellular respiration (more specifically- glycolysis).

Civic
Country A has always focused on producing cotton. Country B is a producer of coffee, grain, and textiles. Based only on this information, which statement is true about these two countries? (1 point) Country A exports more than Country B. Country A has a more diversified ...

Social Studies
How is affirmative action related to education and students?

Social Studies
I found to things: 1) that it limited the number of immigrants in the country 2) that it required a certain number of minority to be hired. Which one of the two is it?

Social Studies
What is a quota system?

Social Studies
What is affirmative action?

English
I think your topic sentences are okay, but you need to put more description in it. They need to flow so no one would get lost while reading. Make sure these facts are true and not what you think it is overall.

English
Hi can you check my topic sentences? Antigone and Creon argue as she fights for the gods and he fights for his beliefs, resulting in the division of the city. Despite of the many warnings he receives, Creon’s discounting of prophecy produces destruction due to his ...

Algebra 1
Subtract them so the x's cancel out. Then solve for y, and plug it back in.

Geometry
Find the area of the circle than multiply it by the height to get your answer.

science
A lever scale is balanced with a beaker filled of air on one side. The scale is very sensitive and can easily measure a change in weight of about 1/2 mg. What happens If you put your finger carefully into the beaker without touching the glass?

physical science
Vi up = 10 sin 60 = 8.66 m/s if ax is horizontal acceleration, there is none. Horizontal component of velocity is constant

science
Hello Damon i have asked my teacher and he said that the air part is not what you said. He gave me one more chance to tell him what is the right answer.

science
A lever scale is balanced with a partially filled glass of water on one side. Will the balance be upset (and if so how?) if you put your finger carefully into the water without touching the glass? What happens if the beaker is filled with air instead of water?

English
ok thank you.

English
What is the tone in "The Bungrass Edge of the World" By Annie Proulx?

English
thank you. You should read it. it is interesting

English
would the tone for "The Life You Save May Be Your Own" by Flannery O'Conner be selfish because Mr. Shiftlet wants the car only and the mother is looking for any man to hand her daughter to?

College
What id the difference between University of maryland college park and University of Maryland Baltimore? I know they are at different locations but which one has what? I looked online but got so many different answers that i got confused.

Health/profession
thank you

Health/profession
when i looked at UMD, it said Pre-Medicine (Allopathic, Osteopathic, Optometry, Podiatry). What does that mean? I looked up the words, but I don't know why it is placed there though.

Health/profession
If I wanted to become a cardiovascular surgeon, would I take pre-medicine for osteopathic?

physics
A merry-go-round (pictured) is sitting in a playground. It is free to rotate, but is currently stationary. You can model it as a uniform disk of mass 200 kg and radius 110 cm (consider the metal poles to have a negligible mass compared to the merry-go-round). The poles near ...

pre-algebra

eng 1511
He thought that he could afford to pay his own school fees.

Two six sided dice were rolled, and a friend tells us that the numbers that came up were identical. Find the probability that the sum of the numbers was as follows: a) 4 b) 11 c) an even number d) an odd number

math
1/3 probability

math
John has 2 coins, one fair and the other unbalanced so that the probability of its coming up heads is 2/3. He picks one of the coins at random, tosses it, and it comes up heads. What is the probability that he picked the unbalanced coin?

math
Three boxes, labeled A,.B. C, contain 1 red and 2 black balls, 2 red and 1 black balls, and 1 red and 1 black ball, respectively. Compute the terminal probabilities by using the multiplication technique. Then add the terminal probabilities for all the outcomes in which the ...

math
A card is drawn from an ordinary deck of 52 cards, and the result is recorded on paper. The card is then returned to the deck and another card is drawn and recorded. Find the probability that the following occurs: a) the first card is a diamond b) the second card is a diamond ...

algebra
a) 143/5544 b) 2808/5544 c) 2736/5544

So what I think is that first you havr to add 4 to the number you are starting with and keep on going. Basically you are skip counting by 4 but is starting on the number you are given.

English-CItation
MLA 7th edition..I am using citation machine I don't know which one of the categories I need to use because I need to show the pages too...

math
On three tests you earned grades of 88%,94% and 90%. Each test was worth 150 points. The final exam is worth 250 pts. How many pts do you need on the final exam to earn 93% of the total points on tests? What percent do you need on the final?

math
The final exam is worth 250 points. How many points do yu need on the exam to earn 93% of the total points ? What percent do yu need on the final?

math
how do you get the percent of 1 over 12

Algebra
The equation is 5= -z - 3 Why is the answer -8 and not just positive 8? Please explain the whole negative variable thing.

US HISTORY
the us supreme court

Chemistry
What mass of ice would you have to add to water to get the same change in temperature as if you add 7.55 grams of dry ice to water if they both started at the same temperature?

physics
a 43.7 kg student runs down the sidewalk and jumps with a horizontal speed of 4.48 m/s onto a stationary skateboard. the student and the skateboard move down the sidewalk with a speed of 4.25m/s. find the mass of the skateboard in units of kg. how fast would the student have ...

physics
a 43.7 kg student runs down the sidewalk and jumps with a horizontal speed of 4.48 m/s onto a stationary skateboard. the student and the skateboard move down the sidewalk with a speed of 4.25m/s. find the mass of the skateboard in units of kg. how fast would the student have ...

physics
a 43.7 kg student runs down the sidewalk and jumps with a horizontal speed of 4.48 m/s onto a stationary skateboard. the student and the skateboard move down the sidewalk with a speed of 4.25m/s. find the mass of the skateboard in units of kg. how fast would the student have ...