# Ethan

Most popular questions and responses by Ethan-
## Chemistry

Consider the voltaic cell Zn(s) + Cu{2+}(aq)--> Zn{2+}(aq)+Cu(s) {}=charge Under standard conditions, what is the maximum electrical work, in Joules that can accomplish if 60 g of copper is plated out?

*asked on April 15, 2012* -
## Social Studies

What is a reason that the Missouri Compromise did not have lasting effects? Please Help A.It only applied to the lands of the Louisiana Purchase. B.It only applied to the lands of the Mexican Cession. C.It relied on popular sovereignty. D.It limited the

*asked on February 27, 2018* -
## Calculus

If a ball is thrown in the air with a velocity 44 ft/s, its height in feet t seconds later is given by y = 44t - 16t2. (Round your answers to one decimal place.) (a) Find the average velocity for the time period beginning when t = 2 and lasting 0.5 second.

*asked on January 17, 2011* -
## Social studies

What is the main topic discussed in the Analects of Confucius?

*asked on October 3, 2018* -
## Chemistry 1 Honours

When copper(II) nitrate reacts with sodium hydroxide, copper (II) hydroxide is produced. How many grams of Cu(OH)2 can be prepared from 12.7g of Cu(NO3)2 and excess NaOH?

*asked on February 4, 2018* -
## Chemistry

A voltaic cell utilizes the following reaction and operates at 298K 3Ce{4+}(aq)+Cr(s)--->3Ce{3+}(aq)+Cr{3+}(aq) {}=Charge What is the EMF of this cell under standard conditions? What is emf of cell when [Ce{4+}]=2.1M, [Ce{3+}]=.13M, and [Cr{3+}]=2.0*10^-2

*asked on April 15, 2012* -
## Chemistry AP

Calculate the pH of a 0.44 M aqueous solution of NH4Cl. Kb = 1.8 × 10−5 . I've tried used the Ka=Kw/Kb equation then used the resulting 5.5e-10 in Kw=([H+][Cl-])/[NH4Cl] , using that to get the [H+], but it isn't correct and I don't know what else to

*asked on February 5, 2015* -
## math

translation of the quotient of 100 and w

*asked on August 30, 2015* -
## Physics

A 20-kg child running at 1.4 m/s jumps onto a playground merry-go-round that has inertia 180 kg and radius 1.6 m. She is moving tangent to the platform when she jumps, and she lands right on the edge. Ignore any friction in the axle about which the

*asked on October 19, 2015* -
## Math | Algebra

Brand A granola is 25% nuts and dried fruit and brand B granola is 20% nuts and dried fruit. How much of sweet item A and sweet item B should be mixed to form a 20-lb batch of sweets that is 23% nuts and dried fruit?

*asked on December 14, 2016* -
## Chem

To prepare 20 mL of 15 mM NaCl, how much NaCl would you need to weigh? 2. To prepare 5 mL of 1 mM glucose, how much glucose would you need to weigh? How do you prepare 1 mL of 1 mM NaCl using the NaCl solution you prepared in (1)? 3. How do you prepare 1

*asked on September 30, 2018* -
## Physics

Karen has a mass of 62.60 kg and she rides the up escalator at Woodley Park Station of the Washington D.C. Metro. Karen rode a distance of 62 m, the longest escalator in the free world. How much work did the escalator do on Karen if it has an inclination

*asked on January 31, 2012* -
## Physics

A startled armadillo leaps upward, rising 0.515 m in the first 0.203 s. (a) What is its initial speed as it leaves the ground? (b) What is its speed at the height of 0.515 m? (c) How much higher does it go?

*asked on January 16, 2011* -
## Biology: Genetics

In guinea pig, short hair (L) is dominant to long hair (l) and the heterozygous condition for yellow coat (Y) and white coat (y) gives cream coat. A short haired guinea pig is bred to long haired white guinea pig and one of the offspring is a long haired

*asked on February 4, 2014* -
## Language arts

List some important ideas that the cay includes. Why did you choose those ideas?

*asked on December 10, 2018* -
## Science

1.What challenges does pesticides pose to biodiversity? 2.What do you think should be done and why? Can someone help me plz!! i have to write a discussion.

*asked on November 27, 2018* -
## Algebra

A company charges $6 to make an pattern for an order of T-shirts and $11 for each T-shirt it produces from the pattern. The expression $11n+$6 represents the cost of n T-shirts with the same pattern.Find the total cost for 5 T-shirts with the same

*asked on November 30, 2015* -
## Calculus

The widths (in meters) of a kidney-shaped swimming pool were measured at 3-meter intervals as indicated in the figure. Use the Midpoint Rule with n = 4 to estimate the area S of the pool if a1 = 15.5, a2 = 18, a3 = 17, a4 = 14, a5 = 12.5, a6 = 12, and a7 =

*asked on November 9, 2011* -
## Algebra

Which of these numbers is not rational? A. 3 squared B. .25 C. 1/5 D. 9 squared

*asked on September 11, 2017* -
## Finance

You find the following Treasury bond quote. To calculate the number of years until maturity, assume that it is currently May 2016. The bonds have a par value of $1,000. Rate Maturity Mo/YR Bid price Ask price Chg Ask Yld 5.374 May 30 104.4991 104.6448

*asked on July 23, 2018* -
## Chemistry

A 0.8870-g mixture of sodium chloride and potassium chloride is dissolved in water and silver nitrate is added. The AgCl that precipitates has a mass of 1.913 g. Calculate the percent by mass of potassium in the initial mixture。

*asked on November 12, 2017* -
## Physics

A chain is held on a frictionless table with 1/3 of its length hanging over the edge. If the chain has length L = 33 cm and mass m = 21 g, how much work is required to pull the hanging part back onto the table?

*asked on February 16, 2011* -
## Statistics

Let the joint density function of the random variables X and Y be f(X,Y)(x,y)= 2xe^(x(^2)-y) for 0

*asked on March 3, 2019* -
## Art

Creating a portrait that embodies a person's feelings or personality involves

*asked on December 4, 2018* -
## Physics

A crew team rows a boat at a rate of 20 km/h in still water. In practice on a river, the team rows for 30 minutes up the river (against the current), and then for 30 minutes down the river (with the current). The speed of the river current is 1.5 km/h. How

*asked on January 19, 2018* -
## English

identify the author's purpose in this passage. Be sure to include: How do you know this is the author's purpose?

*asked on December 5, 2018* -
## Physics

A ﬁgure skater begins spinning counterclockwise at an angular speed of 4.6π rad/s. During a 4.6s interval, she slowly pulls her arms inward and ﬁnally spins at 7.6π rad/s. What is her average angular acceleration during this time interval? Answer in

*asked on March 28, 2012* -
## chemistry

Sodium phosphate, Na3PO4, reacts with HCl to form H3PO4 and NaCl. How many liters of 0.1 M HCl are required to react with 0.1 mole of sodium phosphate?

*asked on October 13, 2008* -
## Calculus

An architect wants to design a window in the shape of a rectangle capped by a semicircle. If the perimeter of the window is constrained to be 24 feet, what dimensions should the architect choose for the window in order to admit the greatest amount of

*asked on February 6, 2016* -
## Chemistry AP

Calculate the concentration of H3O + present in 0.377 M H2CO3. Answer in units of mol/L I know the Ka of H2CO3 is 4.3E-7. But I don't know what to do from there. (Or, I'm not getting the correct answer at least)

*asked on February 9, 2015* -
## AP Chemistry

What is the value of w (work) when 1.3 moles of H2 expands from 25 liters to 50 liters against a constant external pressure of 1 atm, then expands further from 50 to 100 liters against a constant external pressure of 0.1 atm? Answer in calories. Answer in

*asked on January 6, 2015* -
## Geometry

What is the radius of a cylinder with a volume of 432pi cm^3 if the height of the cylinders is equal to its diameter?

*asked on May 8, 2018* -
## Statistics

8. A tetrahedron shaped die gives one of the numbers 1, 2, 3, 4 with equal probabilities. We roll two of these dice and denote the two outcomes by X1 and X2. Let Y1 =(minpX1, X2) and Y2 = |X1 - X2|. (a) Find the joint probability mass function of X1 and

*asked on March 3, 2019* -
## Chemistry AP

Hey Bob, What is the pH at the point during a titration when 20 mL of 0.200 M HCl has been added to 30 mL of 0.0500 M NH3 solution? HCl is strong acid, Kb = 1.8 × 10−5 for NH3. Answer in units of pH. I've gone about getting the mmol of HCl and NH3,

*asked on February 20, 2015* -
## science

Cypress pond

*asked on December 4, 2018* -
## Health

Is it normal not to have nocturnal emissions?

*asked on May 25, 2018* -
## Physics

A unit of area often used in measuring land areas is the hectare, defined as 104 m2. An open-pit coal mine consumes 99 hectares of land, down to a depth of 28 m, each year. What volume of earth, in cubic kilometers, is removed in this time?

*asked on January 12, 2011* -
## math

A video rental company offers a plan that includes a membership fee of $8 and charges $2 for every DVD borrowed. They also offer a second plan, that costs $14 per month for unlimited DVD rentals. If a customer borrows enough DVDs in a month, the two plans

*asked on April 23, 2015* -
## English

The fifth grade class was 3/5 boys. Of those boys, 4/6 had brown hair. What fraction were boys and had brown hair?

*asked on May 25, 2016* -
## Math

David and Coda-Wayne are walking a trail. Ted walks 3.1 kilometers farther than David. Write an expression and solve for X.

*asked on December 3, 2018* -
## Physics

A diver performing a double somersault spins at an angular speed of 4.5 π rad/s precisely 0.70s after leaving the platform. Assuming the diver begins with zero initial angular speed and accelerates at a constant rate, what is the diver’s angular

*asked on March 28, 2012* -
## Chemistry

In a 1.0× 10–4 M solution of HClO(aq), identify the relative molar amounts of these species from most to least: HClO, OCl, OH^-, H30^+, H20

*asked on February 21, 2013* -
## Chemistry

Calculate the cell potential for this voltaic cell at 298K if it is constructed using solutions of .25M Ni(NO3)2 and .01M Cu(NO3)2 Any explanation would be spectacular

*asked on April 23, 2012* -
## Chemistry

Complete and balance the following equation: Cr2O7{2-}(aq)+CH3OH(aq)-->HCO2H(aq)+Cr{3+}(aq) Any feedback would be great, thank you so much.

*asked on April 14, 2012* -
## Physics

Because Earth's rotation is gradually slowing, the length of each day increases: The day at the end of 1.0 century is 1.0 ms longer than the day at the start of the century. In 72 centuries, what is the total (in hours) of the daily increases in time (that

*asked on January 12, 2011* -
## Algebra

The foot of an extension ladder is 9ft from a wall. The height that the ladder reaches on the wall and the length of the ladder are consecutive integers. How long is the ladder?

*asked on June 15, 2018* -
## Math

An object is thrown directly downwards from a height of 60m with an initial velocity of 11m/s. What will be its velocity on impact with the ground?

*asked on December 4, 2018* -
## Physics

An object is dropped from rest. What is its instantaneous speed when it has been in motion for 7 s? The acceleration of gravity is 9.8 m/s 2 . Answer in units of m/s

*asked on March 16, 2013* -
## Physics

At a county fair, a boy takes his teddy bear on the giant Ferris wheel. Unfortunately, at the top of the ride, he accidentally drops his stuffed buddy. The wheel has a diameter of 14.6 m, the bottom of the wheel is 2.4 m above the ground and its rim is

*asked on June 14, 2012* -
## English

in his famous speech at the march on washington in 1963, dr. martin luther king jr. said, i have a dream that my four little children will one day live in a nation where they will not be judged by the color of their skin but by the content of their

*asked on December 17, 2018* -
## English

What does Taylor want young people to "know and understand"?

*asked on December 17, 2018* -
## science

Which of the following would be the limiting reagent in the reaction shown below? There are 50 molecules of O2 and 50 molecules of H2. 2H2(g) + O2(g) ==> 2H2O(g)

*asked on November 13, 2009* -
## math

translation for y less than 18 times 6

*asked on August 30, 2015* -
## Chemistry

A voltaic cell utilizes the following reaction and operates at 298K 3Ce{4+}(aq)+Cr(s)--->3Ce{3+}(aq)+Cr{3+}(aq) {}=Charge What is the EMF of this cell under standard conditions? What is emf of cell when [Ce{4+}]=2.1M, [Ce{3+}]=.13M, and [Cr{3+}]=2.0*10^-2

*asked on April 15, 2012* -
## Physics

This is a projectile motion question. A ball with a mass of .4 kg, initially at rest is kicked directly toward a 3 meter fence from a point 20 meters away. The initial velocity is 17 m/s at an angle of 35 degrees. The ball is hit by nothing and there is no

*asked on October 13, 2012* -
## Finance

You have arranged for a loan on your new car that will require the first payment today. The loan is for $38,500, and the monthly payments are $690. If the loan will be paid off over the next 69 months, what is the APR of the loan? (Do not round

*asked on July 20, 2018* -
## Math

An architect is designing an atrium for a hotel. The Atrium is to be rectangular with a perimeter of 728ft of brass piping. What dimensions will maximize the area of the atrium?

*asked on June 12, 2018* -
## math

0.(-7)=

*asked on September 18, 2019* -
## Chemistry Ap

At 20◦C the vapor pressure of pure methanol (CH3OH) is 89.0 torr and of pure water (H2O) is 17.5 torr. A solution of methanol and water has a total vapor pressure of 35.5 torr at 20◦C. Calculate the mole fraction of methanol in this solution. Assume

*asked on March 3, 2015* -
## Physics

During a hard sneeze, your eyes might shut for 0.58 s. If you are driving a car at 92 km/h during such a sneeze, how far does the car move during that time?

*asked on January 16, 2011* -
## Calculus

The monthly cost of driving a car depends on the number of miles driven. Lynn found that in May it cost her $410 to drive 300 mi and in June it cost her $470 to drive 600 mi. (a) Express the monthly cost C as a function of the distance driven, d, assuming

*asked on January 17, 2011* -
## algebra

How would I find three different quotients that equal 5 to the negative 7th

*asked on February 5, 2010* -
## Chemistry AP

Alright, this time, I know I have not mistyped my answer. Find the initial concentration of the weak acid or base in an aqueous solution of hydrazine (NH2NH2) with a pH of 10.16. Kb = 1.70 ×10−6 Answer in M I've tried going from 10^-pH then using that

*asked on February 9, 2015* -
## pre-cal

Find the EXACT VALUE of csc(-11pi/12) If that angle is in radians, it is easy. A full circle has 2PI radians...or 360 deg so 22PI/24 is the same as 22*15 deg, or -30 deg. The 30 deg triangle is well known. The sin is 1/2, so the csc is 2 Figure out the

*asked on May 16, 2007* -
## algebra

(x4 − 9x + 5x7) + (5x − 10 + 3x4 − 2x2)

*asked on October 12, 2019* -
## Chemistry

4Fe + 3O2 = 2Fe2O3 158g of Fe will react with how many litres of O2 to produce the maximum amount of Fe2O3

*asked on December 11, 2016* -
## Algebra

How do you write the expression that represents the total length of each segment

*asked on January 20, 2016* -
## Chemistry AP

At 20◦C the vapor pressure of pure methanol (CH3OH) is 89.0 torr and of pure water (H2O) is 17.5 torr. A solution of methanol and water has a total vapor pressure of 35.5 torr at 20◦C. Calculate the mole fraction of methanol in this solution. Assume

*asked on March 3, 2015* -
## LA

@Ms.Sue Im a person that was looking to help people in la and i found a post that gave all the answers to the connexus page La and the way i reconize it is when i was in 8th that was the program i used, can you shut down the post it was posted at Friday,

*asked on May 22, 2018* -
## Physics

A certain diving bell for use in the ocean has a square window measuring 0.250 m on each side. The inside of the bell is pressurized and maintained at a pressure of 2.00 atm. The mass density of seawater is 1025 kg/m3. How deep can this bell be lowered

*asked on December 6, 2015* -
## o level mathematics

in a class of 35, all the pupils play at least 1 game, volleyball, netball and hockey. volleyball only 10, those who play netball only 5, those who play hockey only 3, if 2 play all 3 games how many altogether play volleyball

*asked on March 6, 2015* -
## physics

A 4.9 g bullet leaves the muzzle of a rifle with a speed of 332 m/s. What force (assumed constant) is exerted on the bullet while it is traveling down the 0.85 m long barrel of the rifle?

*asked on September 24, 2008* -
## Math

A train leaves the station and travels north at a speed of 75 mph. Two hours later, a second train leaves on a parallel track and travels north at 125 mph. How far from the station will they meet?

*asked on July 10, 2018* -
## Chemistry AP

Calculate the pH of a 0.44 M aqueous solution of NH4Cl. Kb = 1.8 × 10−5 . I've tried used the Ka=Kw/Kb equation then used the resulting 5.5e-10 in Kw=([H+][Cl-])/[NH4Cl] , using that to get the [H+], but it isn't correct and I don't know what else to

*asked on February 5, 2015* -
## pre-cal

Simplify the given expression........? (2sin2x)(cos6x) sin 2x and cos 6x can be expressed as a series of terms that involve sin x or cos x only, but the end result is not a simplification. sin 2x = 2 sinx cosx cos 6x = 32 cos^6 x -48 cos^4 x + 18 cos^2 x -

*asked on May 17, 2007* -
## Math

Expand [1+x^2(1+x)]^7 in ascending powers of x as the term in x^8.

*asked on October 2, 2011* -
## Physics

A 40.7kg wagon is towed up a hill inclined at 18.1 degrees with respect to the horizontal. The tow rope is parallel to the incline and has a tension of 139N in it. Assume that the wagon starts from rest at the bottom of the hill, and neglect friction. The

*asked on February 15, 2012* -
## Biology

Hey just wondering if you think my answers right, 1)Biological safety cabinets are not required when working with containment level (blank) materials a) 1, b)2, c)3, d)4 - answer a? 2)Materials in Risk Group (blank) pose the least risk to the individual

*asked on September 11, 2018* -
## Math

A train leaves a station and travels north at a speed of 75mph. Two hours later, a second train leaves on a parallel track and travels north at 125mph. How far from the station will they meet?

*asked on June 11, 2018* -
## Math

1. Daniel wants to save at least 20 dollars by putting pennies in a jar daily. On first day, he puts one penny into the jar. The second day he puts 2 pennies into the same jar. On the nth day he pus n pennies into the same jar. Which day is the first day

*asked on February 22, 2015* -
## math

Two investments earn a total annual income of $2825. One investment is in a 6.75% annual simple interest certificate of deposit. The other is in a 7.25% tax free annual simple interest account. The total amount invested is 40,000. Find the amount in

*asked on October 3, 2012* -
## Chem

To prepare 5 mL of 1 mM glucose, how much glucose would you need to weigh? How do you prepare 1 mL of 1 mM NaCl using the NaCl solution you prepared in I get you would use c=n/v and get grams. But how would you answer the second part of the question?

*asked on September 30, 2018* -
## Physics

A train is traveling south at 23.5 m/s when the brakes are applied. It slows down with a constant rate to a speed of 5.01 m/s in a time of 8.73 s. How far does the train travel during the 8.73 s? I have already found -Acceleration during braking: -2.12m/s

*asked on September 16, 2015* -
## AP Chemistry

Calculate the entropy change when 4.88 g of H2 reacts with O2 according to the reaction 2H2(g) + O2(g)→2H2O(ℓ)at 298 K and 1 atm pressure. The standard molar enthalpy of formation of H2O(ℓ)at 298 K is −285.8 kJ/mol. The corresponding free energy of

*asked on January 20, 2015* -
## Calc

A cylindrical slime tank is placed so that the axis of the cylinder is horizontal. Find the fluid force on a circular end of the tank if the tank is half full, assuming that the diameter is 6 feet and the slime weighs 54 pounds per cubic feet?

*asked on December 14, 2013* -
## Chemistry

Cytochrome, a complicated molecule that we will represent as CyFe2+, reacts with the air we breathe to supply energy required to synthesize adenosine triphosphate (ATP). At pH 7.0 the following reduction potentials pertain to this oxidation of CyFe2+:

*asked on April 15, 2012* -
## Physics

A car travels up a hill at a constant speed of 33 km/h and returns down the hill at a constant speed of 60 km/h. Calculate the average speed (in km/h) for the round trip.

*asked on January 16, 2011* -
## English

What is the 3rd step In the multi step draft reading

*asked on September 30, 2019* -
## math

Find the smallest positive integer n for which 126n cube root is a whole number

*asked on September 10, 2015* -
## Calculus

When a particle is located a distance x meters from the origin, a force of cos(x/4) newtons acts on it. How much work W is done in moving the particle from x = 1 to x = 3?

*asked on December 4, 2011* -
## Physics

An electric vehicle starts from rest and accelerates at a rate of 2.3 m/s2 in a straight line until it reaches a speed of 17 m/s. The vehicle then slows at a constant rate of 1.4 m/s2 until it stops. (a) How much time elapses from start to stop? (b) How

*asked on January 16, 2011* -
## chemistry

A precipitate of calcium phosphate is formed when aqueous solutions of sodium phosphate and excess calcium chloride are mixed. If 100.0 mL of 1.5 M sodium phosphate solution is the limiting reactant, how many grams of calcium phosphate can be expected?

*asked on September 3, 2010* -
## Calculus II

Find the centroid (x¯,y¯)(x¯,y¯) of the region bounded by: y=5x^2+6x y=0 x=0 x=6 I know the integral (think, at least) is from 0 to 6 and between the first and second equation given, but I missed this lecture and have no idea how to find the center of

*asked on February 19, 2017* -
## Calculus

lim sin2x x->0 ----- x How do I get rid of the x on the bottom in order to solve this problem? Thanks!

*asked on May 14, 2011* -
## physics

Two stars are 4.40 1011 m apart and are equally distant from the earth. A telescope has an objective lens with a diameter of 1.03 m and just detects these stars as separate objects. Assume that light of wavelength 550 nm is being observed. Also assume that

*asked on April 18, 2014* -
## Physics

An 845-N sled is pulled a distance of 190 m. The task requires 1.70 104 J of work and is done by pulling on a rope with a force of 124 N. At what angle is the rope held?

*asked on January 31, 2012* -
## trigonometry

A tent pole is 85 feet high. A cable is attached to the ground 200 feet from the tower base. How long is the cable? What is the measure of the angle the cable makes to the ground?

*asked on May 26, 2014* -
## Physics

An external force F is holding a bob of mass 725 g in a stationary position. The angle that the massless rope makes with the vertical is θ = 33°. (a) What is the magnitude, F, of the force needed to maintain equilibrium in N? (b) What is the tension in

*asked on May 24, 2012* -
## Physics

A girl sitting on a merry-go-round moves counterclockwise through an arc length of 3.36m. If the girl’s angular displacement is 2.96 rad, how far is she from the center of the merry-go-round? Answer in units of m.

*asked on March 28, 2012* -
## Geometry

the measure of an angle is 7 less than 10 times its supplement

*asked on September 27, 2011*