# Posts by Samantha

Total # Posts: 1,686

**chemistry**

10.0 mL of a Cu2+ solution of unknown concentration was placed in a 250 mL Erlenmeyer flask. An excess of KI solution was added. Indicator was added and the solution was diluted with H2O to a total volume of 75 mL. The solution was titrated with 0.20 M Na2S2O3. The equivalence...

**Or**

or would it be 9(sin theta - 5/9) i believe i did the work wrong

**Follow up work.. I am unsure if it is the right**

I know i would bring the 5 over to the other side so it would look like x = 9sin theta - 5 would I distribute the 9 to the sin and the -5? So x = 9(sin theta - 45) just confused on how to get to cos 2 theta

**Math**

A bag contains 6 red balls, 5 green balls and 4 yellow balls. How many balls must you take out to be sure that you have at least 3 balls of each color? I literally have no idea for this question. Should I just put 15(take all of them out to be sure?) or is there some kind on ...

**UNION UNIVERSITY**

Find the Z score for the weights of Middle school boys which are approximately Normal, mean = 130 lbs, Standard Deviation = 7, if Johnny weighs 148 lbs, What's his Z score?

**Physics**

NASA, when it sends probes to other planets, uses what is known as a gravitational slingshot. This is when a probe uses the gravitational potential energy a planet to gain kinetic energy. Even though the probe and the planet are not physically colliding, one can treat this ...

**Physics**

A block of mass 0.45 kg can slide over a frictionless horizontal surface. It is attached to a spring whose stiffness constant is k = 18 N/m. The block is pulled 38 cm and let go. a)What is its maximum speed? b)What is its speed when the extension is 30 cm? c)At what position ...

**sixth grade math**

Hffuh

**grammar**

them

**global studies**

Like many absolute monarchs before him, Peter the Great strengthened his own power by limiting the power of Russian

**Chemistry 104**

A student has 10.0mL of phosphate solution that contains 1.0M PO4{3-}.The Student reacts this with excess ammonium & magnesium under basic conditions to produce 2.2034g of struvite. Calculate the % yield.

**Math**

Each letter in this addition problem stands for a different digit, but every letter stands for the same digit everywhere it appears. For example, all of the C's stand for the same digit. Reconstruct the problem to find the value of SCENE. CUTS +CUTS ------ SCENE

**5th grade math**

You are correct 10

**Math**

Logan saves $5.50 in dimes and quarters over a week. He has 20 more dimes than quarters. Find the number of dimes and quarters he saves. How do I solve the problem algebraically?

**chemistry**

Can someone please explain to me how to find the energy released? Given the overall reaction that takes place when hydrogen is burned in a young star, how much energy in MeV is released per He nucleus formed? masses: 1-H atom= 1.007amu 4-He atom= 4.002 amu positron = 5.485e-4 ...

**Pre-Calculus**

it says webpage not found

**Chemistry**

244pm

**Algebra 3-4**

The first stage of a rocket burns 28 s longer than the second stage. If the total burn time for both stages is 152 s, how long does each stage burn? Describe how you found your answer. I was originally thinking to divide 152 by 2 then add 28, but I realized that wouldn't ...

**Physics**

An object has a initial velocity of 10 m/s in the positive x direction. Under a constant acceleration it stops after undergoing a displacement of 148.3 m in the positive x direction. Because it is still under the same acceleration it then travels back in the negative in the x ...

**Math, Calculus**

0.00695

**Math**

Why does Zara have a good driving record?

**math**

Yooyoullylyl

**algebra**

is 3.27 a rational or irrational number

**college statistics**

The CEO of ABC manufacturing commissioned a study to look at the differences between the current salaries of her employees (n = 474) and their starting salaries. The study collected current and beginning salary data for each of the 474 employees and the researcher conducted a ...

**science**

A runner whose mass is 49 kg accelerates from a stop to a speed of 6 m/s in 3 seconds. (A good sprinter can run 100 meters in about 10 seconds, with an average speed of 10 m/s.) (a) What is the average horizontal component of the force that the ground exerts on the runner'...

**physics**

An object with mass 110 kg moved in outer space. When it was at location < 11, -35, -7 > its speed was 17.5 m/s. A single constant force < 230, 420, -230 > N acted on the object while the object moved to location < 16, -41, -13 > m. What is the speed of the ...

**math**

Mike's number is 2000 more than Jerry's which is 400 less than Barry's. Larry's number is 1500 more than Sam's, which is 443. Sam's number is 60 less than Barry's. WHat is each boy's number?

**math**

Mike's number is 2000 more than Jerry's which is 400 less than Barry's. Larry's number is 1500 more than Sam's, which is 443. Sam's number is 60 less than Barry's.

**algebra**

A pet boarding facility wants to build two adjacent pens of equal size. They are using the length of the dog kennel as one side of the two pens. They have 324 feet of fencing to build the pens. What width should he make the pens to maximize the total area of the pens?

**Math**

When rolling a standard number cube twice, what is the probability of rolling two even numbers? I'm pretty sure the answer is 1/4, but the solutions says that this is wrong.

**statistics**

A pop-music record firm wants the distribution of lengths of cuts on its record to have an average of 129 seconds and a standard deviation of 10 seconds so that disc jockeys will have plenty of time for commercials within each 5-minute period. The population times for cuts is ...

**Statistics**

A brewery's filling machine is adjusted to fill bottles with a mean of 33.8 oz. of ale and a variance of 0.005. Periodically, a bottle is checked and the amount of ale noted. (b) Let's say you buy 93 bottles of this ale for a party. How many bottles would you expect to...

**Calculus**

1. If y′= x(1+ y) and y > -1 , then y= A) y=sinx B) y=3x^2+C << C) y=Ce^1/2x^2-1 D) y=1/2e^x^2+C E) y=Csq(x+3) 2. If dy/dx = x cos x^2 and y = −3 when x = 0, when x = π, y = ___. A) -3.215 B) √2 << C) 1.647 D) 6 E) 3π 3. Suppose an ...

**Calculus**

1) yy'-e^x= 0, and y=4 when x=0 means that: A)y=x-lnx^2+4 B)y^2=4x^2+3 C)y=-2x+1/2x^3 D)y^2=2e^x+14 E)1/2ln|x^2+4|+6 2) The rate of change of P with respect to t is directly proportional to (10-t) and inversely proportional to the cube root of P. The differential equation ...

**Calculus**

Which of the following is a separable, first-order differential equation? A) dy/dx= x+y/2x B) dy/dx=x+y/x-y C) dy/dx=sinx << D) dy/dx=xy/x+y E) dy/dx= 2lnxy 2) The differential equation dy/dx=y/x^2 has a solution given by: A) y=C sqrt(x^2+4) B)y=C e^-1/x C)-1/2ex^2+C D) ...

**Calculus**

Thank you!!

**Calculus**

The region R is bounded by the x-axis, x = 1, x = 3, and y = 1/x^3 A) Find the area of R B) B. Find the value of h, such that the vertical line x = h divides the region R into two Regions of equal area.

**Calculus**

Can someone check my answer? The change in the momentum of an object (Δ p) is given by the force, F, acting on the object multiplied by the time interval that the force was acting: Δ p = F Δt . If the force (in newtons) acting on a particular object is given by ...

**math**

15x5=75 82-75=7 Answer~7

**Chemistry**

Long question but its my last one for homework and im stuck on this word problem. Biomass is represented by the empirical formula C60H87O23N12P. Write a balance equation for the oxidation of C60H87O23N12P with O2 to form CO2, H2O, HNO3, and H3PO4 beginning with 1000g of ...

**Math**

22,000/400=55

**English**

He is not only a great baseball player ,but also a fine pianist. Which is correct (a) preposition ( b) adjective (c) correlative (d) adverb

**statistics**

The state bridge design engineer has devised a plan to repair North Carolina's 4420 bridges that are currently listed as being in either poor or fair condition. The state has a total of 13,168 bridges. Before the governor will include the cost of this plan in his budget, ...

**Math 10**

Hello, I did this question for homework, but my teacher said it was wrong and she didn't explain how it was supposed to be done. So could you please tell me how I am supposed to do this step by step? "A baseball is thrown from the top of a building and falls to the ...

**CALCULUS problem**

There are four parts to this one question, and would really appreciate if you could show and explain how you get to the answer, because I tried looking up how to find the answer myself, but nothing made sense. Thank you! 11. The region R is bounded by the x-axis, x = 1, x = 3...

**Math**

Jack bought a sweater at the sale price of $25. The original cost of the sweater was $40. What percent represents the discount that he received when buying the sweater?

**Math 2**

15

**physics**

A soccer player kicks a ball straight up into the air at 6m.s per second.Ignore air friction. 1.What is the height of the ball at its highest point 2.What is the ball's acceleration at its highest point 3.Calculate the maximum height reached by the ball

**physics**

A soccer player kicks a ball straight up into the air at 6m.s per second.Ignore air friction. 1.What is the height of the ball at its highest point 2.What ie the ball's acceleration at its highest point 3.Calculate the maximum height reached by the ball

**Chemistry**

It says 8. In a similar experiment Mary Moreorlesss was to determine the loss of weight when a crucible of potassium chlorate was heated to drive off the oxygen. After finishing the experiment she concluded the potassium chlorate contained 24.0% oxygen. Why did miraculous(...

**science(CHECK ANSWERS)**

I took this quiz and the answer is B

**Social studies**

No I don't understand...

**Social studies**

Imperialism is to take over

**Social studies**

How is imperialism and the Spanish America war related?

**math**

What does "give a brief explanation as to what kind of solution(s) you expect the linear equation to have: 18x+1/2=6 (3x+25). Transform the equation into a simpler form if necessary" mean?

**math**

What does "give a brief explanation as to what kind of solution(s) you expect the linear equation to have: 18x+1/2=6 (3x+25). Transform the equation into a simpler form if necessary" mean?

**science... PLEASE HELP!**

Could that really be an experiment?

**history**

What are 2 reasons why people moved to the west?

**math**

A triangle has angles described as followed: the first angle is four more than seven times a number, another angle is four less than the first and the third angle is twice as large as the first. What are the sizes of each angle. I got the first angle of the triangle but I am ...

**math**

I do not understand...

**math**

What does "its supplement is twice as large" mean?

**math... PLEASE HELP!!**

The measure of one angle is described as twelve more than four times a number. Its supplement is as twice as large. Find the measure of each angle using an equation.

**math**

Solve the linear equation: x+x+2+x+4+x+6=-28. State the property that justifies your first step and why you chose it. When I solved the equation I got the answer of ×=-10. However, I do not know what the property I need to state for my first step. Isn't it ...

**science... PLEASE HELP!**

What are 5 examples of oganisms that are in the Prostista Kingdom?

**science**

That's the question, it doesn't give any more info. Here is the info: Density of water is 1.o g/cm3 Mass of a penny is 2.5 grams

**science**

Mercury, a metal that is liquid at room temperature, has a density 13.5 times the density of water. How many pennies could your boat hold if we were floating it in mercury instead of water?

**math**

When the problem says "Angel transformed the following equation from 6x+4-×=2 (×+1) to 10=2 (×+1). He then stated that the solution to the equation is ×=4. Is he correct? Explain" when I solved the equation I got 24=10 and 10=10. However, im ...

**math**

When the problem says "Angel transformed the following equation from 6x+4-×=2 (×+1) to 10=2 (×+1). He then stated that the solution to the equation is ×=4. Is he correct? Explain" when I solved the equation I got 24=10 and 10=10. However, im ...

**math**

If the problem says "the sum that shows how many pages Maria read if she read 45 pages of a book yesterday and 2/3 of the remaining pages today." Would the expression/equation be 45 + (2/3)n ?

**math**

Okay, but I have one question. When it says twice the sum how does that look like? Wouldn't it be ____ + ____^2 ?

**math**

What would the expression be if the problem was "the sum of four consecutive numbers." ?

**math**

Correction: what would be the equation if the problem was "The cube of a positive number divided by the square of the same positive number." ?

**math**

What wouldnthenequation benif thenproblem was "The cube of positive number divided by the square of the same positive number." ?

**biology**

Can someone help? I don't understand gene regulation. The regulation of protein synthesis in cells involves the coordination of several different mechanisms. Discuss TWO of the specific mechanisms of gene regulation in eukaryotic cells from the list below and describe how ...

**Math**

Which equation represents the sentence ‘‘d is 17 less than the quotient of n and 4”?

**Math**

Which function rule can be used to represent the area of a triangle with a base b 8 in. longer than twice the height h in terms of the height?

**AP U.S History**

Explain why Britian finally decided against on behalf of the Confeder.

**4 CALCULUS study problem**

Never mind! I solved them all and got them right. :)

**4 CALCULUS study problem**

1. How fast does the radius of a spherical soap bubble change when you blow air into it at the rate of 15 cubic centimeters per second? Our known rate is dV/dt, the change in volume with respect to time, which is 15 cubic centimeters per second. The rate we want to find is dr/...

**LAW**

I would say 2 is A. I am checking on number 1.

**science... PLEASE HELP!**

Is Archaebacteria autotrophic or heterotrophic? Also, is it unicellular or multicellular? I believe it is both autotrophic and heterotrophic and it is multicellular, but I am not sure. Please help!

**P.E /.....**

are you sure? This is important

**P.E /.....**

Ok never mind I figured that too lol. I have this question Im really stuck on Justine would like to improve her speed while dribbling the soccer ball from the defensive to the offensive side of the field. Justine can develop her speed for this type of activity by practicing ...

**P.E /.....**

Two 14-year-old competitive dancers are excited about the upcoming state championships. Their routine has a lot of moves packed into a two minute song the partners execute together. The routine has them covering all four corners of the dance floor in that short time period. ...

**P.E /.....**

Thank you Ms.Sue, but I figured that question out. Will you help me with another?

**P.E /.....**

PLZ PLZ PLZ HELP. Trying to get over quiz Harvey has his heart set on making the state finals for his track team in the 100 yard dash. Although Harvey knows there are many factors to improving his time and becoming an elite sprinter, one skill is paramount to his success. ...

**Connexus P.E**

Harvey has his heart set on making the state finals for his track team in the 100 yard dash. Although Harvey knows there are many factors to improving his time and becoming an elite sprinter, one skill is paramount to his success. This skill is used at the very beginning of ...

**Last two CALC questions. :)**

8. If f(x) = sin(7 − 5x), find f′(π), which is the derivative at π: −0.754 −0.657 0 * 0.657 3.770 9. Given the function: g(x)={x+b, x<0 {cos(x), x≥0 Find the value of b, if any, that will make the function differentiable at x = 0. 0 1...

**Check a few more CALC questions, please?**

I feel pretty good on my answers. Are there any I got wrong? Thank you for the help! 1. If g(x) = tan (5x^2), then g′(x) = * 10x sec2(5x2) sec2(5x2) –10xsec(5x2)tan(5x2) 10sec2(5x2) 7xsec2(5x2) 2. The inflection point of the curve y = x4 − 8x3 + 24x2 + 7x &#...

**Calc help - check rest of answers, please?**

Nevermind, I figured them out! :) Thank you!

**Calc help - check rest of answers, please?**

Thank you so much! I'm getting number 7 as .9%, correct?

**Calc help - check rest of answers, please?**

4. Find the tangent line approximation, L(x), of f(x)=x^2/3 at x = 8. L(x) = 4/3x-20/3 L(x) = 2/3x+8 L(x) = 4(x-8) L(x) = 1/3x + 4/3 *L(x) = 4/3x - 8/3 5. A balloon is rising at a constant speed of 5 ft/sec. A boy is cycling along a straight road at a constant speed of 15 ft/...

**CALCULUS - Check my answers :)**

And 5 would be 25?

**CALCULUS - Check my answers :)**

Is number 4 the last one?

**CALCULUS - Check my answers :)**

I'd appreciate corrections for the ones I get wrong. :) Thanks! 1. Determine which of the following is true for the function f(x) = x^3 +5x^2 - 8x +3. I. f(x) has a relative minimum at x = 2/3. II. f(x) has a relative maximum at x = 2/3. III. f(x) has a zero at x = 2/3 I ...

**Algebra**

During a softball game, a batter hits a ball upward from an initial height of 3 feet. The height, in feet, of the softball is given by s(t)=−16t^2+70t+3 , where t is time in seconds and . Which is closest to the time when the softball will be 50 feet above the ground?

**Geometry**

A softball player asked her father to make her a home plate for a softball game. According to her encyclopedia, an official plate is made from a square by making two 12-inch diagonal cuts upward from both bottom corners. What is the length of the side of the original square?

**English**

What does it mean to be a "critical reader?" Why is this important?

**Statistics**

smith is a weld inspector at a shipyard. he knows from keeping track of good and substandard welds that for the afternoon shift 5% of all welds done will be substandard. If Smith checks 300 of the 7500 welds completed that shift, would it be unusual for Smith to find 30 or ...

**Physical Science**

Why is it important when calculating the distance to extremely distant stars using parallax, astronomers use incredibly accurate instruments?