# Posts by sara

Total # Posts: 4,515

**statistics**

Recent studies, as summarized, for example, in E. Mortensen et al. (2002). The association between duration of breastfeeding and adult intelligence. Journal of the American Medical Ass o ciation , 287 , 2365–2371, suggest that breast-feeding of infants may increase their...

**Math**

If <1 and <2 are supplementary, then <1 and <2 form a linear pair

**Math**

If <1 and <2 are supplementary, then <1 and <2 form a linear pair

**statistics**

The professor teaching a large introductory class gives a final exam that has alternate forms, A, B, and C. A student taking the exam using Form B is upset because she claims that Form B is much harder than Forms A and C. Discuss how percentile point data might be useful to ...

**math**

ok, corrected is 2x^2+4x+4x+8-4=28 2x^2+8x+4=28 2x^2 +8x-24=0 none of them still work

**math**

This is a multiple choice question. What is the solution of the equation 2(x+2)^2-4=28 1)2 only 2)6 only 3)-2 and 6 4)2 and -6 I did (2x+4)(2x+4)-4=28 4x^2+8x+8x+16-4=28 4x^2+16x+12=28 4x^2+16x=16 This is where I get stuck, can you help? thank you

**math**

thank you so I got 45.95, so approx. 46mph, which is still over the speed limit. Thank you for taking the time to check my long involved problem.

**math**

The equation d=0.12v^2 + 2.1v models the distance d in feet it takes a car traveling at a speed of v miles per hour to come to a complete stop. Graces car was able to stop after 350ft on a highway. If the speed limit in the area was 35 miles per hour, was she speeding? Justify...

**Math**

Michael can travel at 166.35mph in his Ferrari. How far can he travel in 5 hours?

**Math**

Colin lived in Scotland and was going to take his caravan on holiday to France. On the first day he travelled 472.87 miles to Portsmouth. He got a ferry which travelled 73.92 miles. He then got off the ferry and drove 134.56 miles to the camp site. How far did Colin travel to ...

**9th grade English**

Thank-you. I guess I shouldn't complain but I want to challenge myself

**9th grade English**

Sam had to mix __________ parts of the two chemicals for the experiment. a. equaled b. equitably c. equal d. equate f. equation I pick C This seems to easy am I missing something?

**Story section**

Imagine you are an old ragged doll.You have just been thrown away by your owner.Tell the story of what happens to you. Please at least write 4 or 5 sentences to make a start Thank you

**Logic**

Thanks

**Logic**

Which of the following is not like the others? A. 1 B. 22 C. -2 D. 50 E. -94

**Logic**

Thank you

**Logic**

Which of the following is not like the others? A. Mars B. Venus C. Asparagus D. Potatoes E. Computers F. Cheeses G. Chairs H. Pasta

**Maths **

A boy spends 1/4 of his money on sweets and 1/3 on computer games. What fraction of his money does he not spend?

**Trigonometry **

The first three terms of an arithmetic progression are 1/2, x, 25. The first three terms of a geometric progression are x+1/4, 32 1/2, and y, where x and y are positive numbers. Find the value of X and the value of Y.

**MATH**

Jenny is running an experiment for organic chemistry class. She needs exactly 100 ml of 70% hydrochloric acid, but the lab only has 90% and 40% solutions. How much of each solutions does she need to mix in order to obtain 100 ml of 70% hydrochloric acid solution?

**Math**

What is 7 to the nearest hundred?

**MATH!!**

There are two numbers whose sum is 50. Three times the first is 5 more than twice the second. What are the numbers?

**math**

15(5^x-2)=8^2x+1 extraneous root sorry for the re post, i typed it wrong

**math**

given f(x) = x^2 and g(x)= squar root x+4. determine the following compostions and their doamin and range a) f(g(x)) b) g-1(superscript) (f(x)) c) g(f(x)) +g-1(superscript)(f(x))

**math**

log(subscript)2 (x+5) + log(subscript)2 (x-1) =4 find the extraneous root

**math**

The pH or acidity of liquid is measured in pH, where pH is given by the equation pH=- log C, with C being the concentration of [H+] in multiples of M=1mol/L. Suppose you are given a solution of hydrochloric acid with a pH of 1.7 and asked to increase the pH solution by 1.4. ...

**math**

opss i typed it wrong 15(5^x-2)=8^2x+1

**math**

15(5x-2)=82x+1 solve the extraneous root

**math**

A polynomial function function is defined by the equation p(x)=3x3+ax2+bx+7, where a, bE/. If p(-2)=5 and p(1)=14 then the value of a+b is...

**Advanced Functions**

4cos2x - cosx-3 =0 0 to 2pi

**chemistry **

The pH or acidity of liquid is measured in pH, where pH is given by the equation pH=- log C, with C being the concentration of [H+] in multiples of M=1mol/L. Suppose you are given a solution of hydrochloric acid with a pH of 1.7 and asked to increase the pH solution by 1.4. ...

**Advanced Functions**

the compound interst forumla is A= P(1+i)^n. consider the function in the form of y= 100(1+x/2)^20, where y is the compound amount. a) determine the required annual interest rate of investment to the nearest tenth of a percentage of 10 years that will give an amount of $300 b...

**statistics**

the percentage increase in price of four items from what they did a year earlier is 72,108,36 and 96 what is the average percentage increase in price of the four items

**physics**

suppose a car is driven from town A to town B from town B to town C and from town C to town D which have equal distances at average speeds 20km/hr,60km/hr and 120km/hr respectively,what is the average speed for the whole journey

**Advanced Functions**

assume the function f(x) and its inverse f-1(x) are both defined for xer. give a geometric interpretation of the composite function y=f(f-1(x))

**Percentage**

If Safia have 10 percent more cookies than Rohit, how many percent fewer cookies does Rohit have than Safia?

**help math!**

Elisabeti bikes from home to the grocery store and back to pick up in- gredients. On the way to the store, she averages 15 mph. Encumbered by groceries, she averages 10 mph on the way back. What is her average speed for the whole hour?

**help with math!**

Morwen bikes around his neighborhood for an hour. He averages 15 mph for the first 40 minutes, but then he tires and averages 10 mph for the last 20 minutes. What is is his average speed for the whole hour?

**MATH 2**

Elisabeti bikes from home to the grocery store and back to pick up in- gredients. On the way to the store, she averages 15 mph. Encumbered by groceries, she averages 10 mph on the way back. What is her average speed for the whole hour?

**MATH**

Morwen bikes around his neighborhood for an hour. He averages 15 mph for the first 40 minutes, but then he tires and averages 10 mph for the last 20 minutes. What is is his average speed for the whole hour?

**math**

Find two fractions in lowest terms with unequal denominators whose difference is 2/7?

**math**

Sasha is a female my mistake

**math**

In one minute, Sasha takes 43 steps. It takes her 301 steps to travel from her house to the shops. If she leaves home at 10:24,at what time will he reach the shops if he walks steadily?

**Advanced Functions**

The number of bicycles, n, sold at one store in a week is a function of the price, p, in dollars. So n(p) for p > 80. The storeÃ¢â‚¬â„¢s cost, c, in dollars for each bike is a function of the number of bikes the store sells each ...

**math- factoring**

Thank you. I was getting thrown off since the bx is +bx and since x=-13 I wasn't sure if you would change the sign to +13 since the bx was positive.

**math- factoring**

The question is ax^2+bx+c=(2x-7)(x-3) for all values of x, What is the value of b? The teacher went over and said the answer is -13, but I am not sure how she got that. Can you please explain. Thank you! I did the first part (2x-7)(x-3) 2x^2-6x-7x+21 2x^2-13x+21 here x=-13 but...

**Advanced Functions**

Nadia collected the data in the table on the left using a CBR after a ball was dropped. (a) Enter the data into L1 and L2 using a TI-83 Plus. Graph the relation. (b) Without looking at the graph, how do you know that the relation is not linear? (c) Use regression to find the ...

**Linear algebra**

Let L1 be the line passing through the point P1=(?1, ?1, 8) with direction vector ?d1=[1, 0, ?3], and let L2 be the line passing through the point P2=(7, ?11, 14) with direction vector ?d2=[1, 2, ?3]. Find the shortest distance d between these two lines, and find a point Q1 on...

**Algebra**

I have found d, my problem is finding Q1 and Q2 and if you don't want to help it's better not to say anything at all I know how to google thanks!

**Algebra**

can somebody please help me with this question I've spent more than 3 hours on this, still nothing Let L1 be the line passing through the point P1=(2, ?4, ?6) with direction vector ?d1=[1, 0, 2]T, and let L2 be the line passing through the point P2=(?2...

**Calculus**

A bowl is created with circular cross sections so that its radius (in cm) is a function of height (in cm) according to the equation r=4sqrt(h+1). Find the volume of soup that fills the bowl if the bow is 2 cm high.

**Physics**

A thin-walled sphere rolls along the floor. What is the ratio of its translational kinetic energy to its rotational kinetic energy through its center of mass?

**MATH**

1. Show, from the definition, that if A:B::C:D and C:D::E:F then A : B :: E : F.

**HELP MATH**

Mr. Kwon has just enough money to buy only 20 mangoes or only 30 oranges. If he wants to buy equal numbers of mangoes and oranges together, how many of each type can he buy with the money?

**Math**

Mr. Dinkelspiel bought $32.56 worth of stamps. He bought 20 more 19-cent stamps than 50-cent stamps. He bought twice as many 32-cent stamps as 19- cent stamps. How many of each kind did he buy?

**Math**

Mr. Kwon has just enough money to buy only 20 mangoes or only 30 oranges. If he wants to buy equal numbers of mangoes and oranges together, how many of each type can he buy with the money?

**physics**

a car is driving at 95 km/h down a highway when a deer runs infront of the car 80 m ahead. if the driver immediately applies the brakes and slows down at 4.2m/s^2, what happens?

**math**

-7<x-5<2

**math**

curcumference is 2(pi)r 62.8=2(pi)r r=9.995 A=2(pi)rh+2(pi)r^2 =[2*(pi)*(9.995)*60]+[2*pi*(9.995^2)] about 4396 cm^3 OR 43.96 m^3

**Physics**

A steel beam that is 7.00 m long weighs 352 N. It rests on two supports, 3.00 m apart, with equal amounts of the beam extending from each end. Suki, who weighs 595 N, stands on the beam in the center and then walks toward one end. How close to the end can she come before the ...

**Math**

I am six years older than my sister. In five year, her age will be 5/6 of my age then. How old is she today?

**Math**

A large glass of juice contains a mix of half mango juice and half pumpkin juice. A smaller glass contains pure pumpkin juice. If the two glasses are combined in a pitcher, the result will be 60% pumpkin juice. The volume of the small glass is 4 ounces; what is the volume of ...

**Algebra 1**

y=9.1x inverse: x=9.1y

**math**

48.4 (9-2)^2+(-3/5) 49+(-.6)

**Physics**

A flywheel turns through 60 rev as it slows from an angular speed of 2.8 rad/s to a stop. How much time is required for it to complete the first 30 of the 60 revolutions?

**Physics**

What is the linear acceleration of a point on the rim of a 38 cm-diameter record rotating at 33 1/3 rev/min?

**physic**

If an erect person's systolic pressure is measured at 120 mm-Hg at the level of heart, please calculate the arterial systolic blood pressure in the head of this person (in the unit of mm-Hg). Assume that the head is 50 cm above the heart (the density of blood is 1050 kg/m...

**bio**

Imagine you are purifying a protein which accounts for 0.001% of the total protein within a cell. How many steps of purification are required to yield pure protein, assuming a 10 fold purification with each step of purification?

**math**

1.The cost of a telephone call from Wilsonto East Meadow is $0,60 for the first three minutes plus $0.17 for each additional minute. What is the greatest number of whole minutes of a call if the cost cannot exceed $2.50? 2.When John bought his new computer, he purchased an ...

**Math**

Bart is saving to buy a flat screen monitor that costs $345. He has already saved $37. What is the least amount of money Bart a must save each week so that at the end of 11 weeks he has enough money to buy the monitor?

**Chemistry**

Determine the concentration for the following solutions 2.0g KOH is dissolved in water to make 200.0 ml of solution

**Math**

When a class took a math test, 15% of the class failed, 25% made some mistakes (but didn’t fail), and 24 students got perfect scores. How many students were in the class?

**Math**

One of the sides of a parallelogram is 4.2 cm and the altitude to that side is 3.6 cm. Find the perimeter of the parallelogram if the altitude to the other side is 2.4 cm.

**Math**

The area of a parallelogram with a side of 5.6 in is equal to the area of a rectangle with sides 7 in and 8 in. Find the altitude to the given side in the parallelogram.

**biology**

A bacterium has a genome size of 6.0 X 106 base pairs. There is one Origin of Replication (ORI) and each DNA polymerase catalyzes the addition of 1,000 nucleotides/second. How much time is needed to replicate the entire genome?

**Molarity question!! please help urgently!**

Suppose you wanted to produce an aqueous solution of pH = 8.70 by dissolving one of the following salts in water: NH4Cl, KHSO4, KNO2, NaNO3. Use salt KNO2. But at what molarity? Please help!! Thank you!

**Equilibrium concentrations, please help!!!**

Lead metal is added to 0.150 M Cr3+(aq). Pb(s)+2Cr3+(aq)?Pb2+(aq)+2Cr2+(aq). KC=3.2×10?10 What is [Pb2+] when equilibrium is established in the reaction? What is [Cr2+] when equilibrium is established in the reaction? What is [Cr3+] when equilibrium is established in the...

**science, chemistry**

Lead metal is added to 0.150 M Cr3+(aq). Pb(s)+2Cr3+(aq)?Pb2+(aq)+2Cr2+(aq). KC=3.2×10?10 What is [Pb2+] when equilibrium is established in the reaction? What is [Cr2+] when equilibrium is established in the reaction? What is [Cr3+] when equilibrium is established in the...

**Math**

The total cost of producting x radio sets per day is (1/4x^2 + 35x + 25) dollars. The price per set at which they may be sold is ( 50 -1/2x) dollars. What should be the daily output be to obtain the maximum profit? Help!!!

**Algerbra**

Thank you!

**Algerbra**

Please help! Find the vertex of f(x)=x^2+2x-3 Find the vertex of f(x)=x^2-3x+1

**English**

Thanks Mr.Bob

**English**

Which option best describes a main idea of "Kuba Khan" Society tends to fear creative people Creative people are welcome in society Society tends to love creative people< Hail is a problem in many societies

**Sara**

I'm reading different... maybe it's C

**English (sorry)**

I think it's B.

**Math**

Determine a,b and c so that curve y= ax^3 + bx^2 + cx will have a slope of 4 at its point of inflection (-1,-5) Help please!

**Math**

Determine a,b and c so that curve y= ax^3 + bx^2 + cx will have a slope of 4 at its point of inflection (-1,-5) Help please!

**Math**

Determine a,b and c so that curve y= ax^3 + bx^2 + cx will have a slope of 4 at its point of inflection (-1,-5) Help please!

**Math**

Fine the max or min points and the points of inflection for the function y=3x^4 - 10x^3 - 12x^2 + 12x - 7 Can someone help me!!!

**Math**

Find the critical points, and the points of inflection y= (x+1)^2/x Help me please!!!

**Algebra **

what are the coordinates of the vertex of f(x)=-x^2+6x-9 (0,-9) (3,-9) (3,0) (6,0) How do I figure this out?

**ELA**

A just took the quiz it is 1. A 2. C 3. B 4. D 5. C I hope this helps!

**Math (Elementary Linear Algebra)**

Find the general flow pattern of the network. 20<---A |\B__>x(4) |/ 80<---C I believe the system of equations for A,B,&C is-A: x(1)+x(3)=20 B: x(2)=x(3)+x(4) C: 0=x(1)+x(2) Assuming flows are all nonnegative, what is the largest possible value for x(3). Sorry, this ...

**Math**

I set up the equation like you said 11+.21m =20+.10m -.10m. -.10m 11+ .11m =20 -11. -11 .11m/.11=. 9/.11 This doesn't seem correct

**Math**

Verizon has two different cell phone plans. The cost, Y, of plan A is $11 a month Plus $.21 per minute. The cost, Y, of Plan B is $20 a month plus $.10 per minute. After how much time to the nearest minute will the cost of plan a B equal to the cost of Plan B? Can you help me ...

**PE**

Which is correct?

**PE**

I took the test and Dairy is correct, if you look at my plate it says the same :)

**math**

For what values of r does the function y = erx satisfy the differential equation y'' ? 6y' + 3y = 0?

**Math discussion**

yea thanks Katie you are really a big help! i just did my discussion and pass it! Katie you are the best. Again thank so much!