# Posts by lauren

Total # Posts: 1,896

**Chemistry **

Write the net ionic equation for the following reaction : Na3SO4(aq) + Ba(NO3)2(aq) —> BaSO4 (s) + 2 NaNO3(aq)

**Chemistry **

In the 18th century Lavoisier experimented with oxides, such as CO2 and SO2. He observed that they formed acidic solutions. His observations led him to infer that tot exhibit acidic behavior, a substance must contain oxygen. However, today that inference is known to be ...

**Chemistry **

Confused on these, please explain or show work for the answer if you can. :) 1. What is the morality of a water solution that freezes at -0.633°C? 2. What is the freezing point of a solution that contains 1.99 g of a molecular solute of molar mass 58.5 g/mol in 58.0 g ...

**Chemistry **

The volume of a balloon is 1 liter at 1 atm pressure and 0°C temperature. What volume is the ballooon at 2 atm pressure and 273°C temperature?

**Chemistry **

Calculate the volume of 1.86M Na3PO4 solution that can be prepared from 5.45 g of Na3PO4

**Chemistry**

Suppose that 2.00mL of 0.02 mol/L aqueous sodium sulphide, Na2S is used to test a 60.0mL sample of water containing 0.0004 mol/L mecury (II) nitrate Hg(NO3)2, ions. a. Write the balanced equation Hg(NO3)2 + Na2S = HgS + 2NaNO3 b. Determine the limiting reactant Na2S = 2.00mL/...

**math**

Name the congruent angles and sides for the pair of congruent triangles. ?MGB ? ?WYT

**math**

Find the measures of the sides of ?ABC and classify the triangle by its sides. A(3,-3), B(1,4), C(-1,-1)

**Chemistry **

If E=hv and h is joules per second and v is waves per second, the end unit is J/s^2, but E can only be Joules, not s^2. How do I fix this?

**Reading books**

How many books a 5th grader should read in a week to excel reading level?

**Chemistry**

Ricky uses ruler c to get a measurement of 3.19. His classmates thought he was wrong because his second digit was not 2. ( the picture shows an object at about 3.2 cm).

**Chemistry**

Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) ---> 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) must be used to produce 15.0g of molten iron.

**Chemistry**

Over the years, the thermjte reaction has been used for welding railroads, in incendiary bombs, and to ignite solid fuel rocket monitors. The reaction is Fe2O3(s) + Al(s) ---> 2Fe(l) + AI2O3(s). What mass of iron (iii) oxide(rust) must be used to produce 15.0g of molten iron.

**Chem HELP!**

The second part is this. The theoretical value for the ration of moles of F to moles of Pt is (exactly) 4. Calculate the percent error for the experimental value found in 3d.

**Chem**

When 5.49 g of platinum reacts with an excess of fluorine, 7.65 g of platinum(_) fluoride forms. a. What is the mass of fluorine in the compound? b. Find the number of moles of platinum that reacted. c. Find the number of moles of fluorine that reacted. d. Calculate the ratio ...

**Math**

Jena is comparing prices of different cell phones. She made a dot plot to show the prices. How can she find the most common price? A) Find the dot all the way to the right. B) Find the dot all the way to the left. C) Find the shortest stack of dots. D) Find the tallest stack ...

**College Algebra**

00 is infinity 6. x\ge \:-2 or x>5 Interval notation (-00, -2] U (5,00) what will be the plotting points on the number line. 7. (-00,1]U (3,00) what will be the plotting points on a number line. 8. (-00,-2)U(8,00)what will be the plotting points on a number line. 9. [-00,-6...

**Math**

Whay 1/4 and 3/4 have 2 pancakes or dots? I think 3/4 should be 6 pancakes.

**Math**

I am confused with this question. A breakfast chef uses three different amounts of milk when making pancakes, depending on the number of pancakes ordered. The dot plot shows Customer's orders for pancakes one morning. How much milk does the chef need to make all the ...

**Math**

Thank you so much!!!

**Math**

How do I show model to multiply 0.16*0.5? I did try by shading .16 over 0.5 but it giving me .10 answer. I need my answer 0.08. Plz help me what I am doing wrong.

**Math**

Graph the inequality on the numberline and then write it in interval notation. 5/3y < 10

**College Algebra**

Graph the inequality on the number line and then write it in interval notation. Y+1/2?2/3.

**Math**

The ice rink sold 94 tickets for the afternoon session, for a total of $778. General admission tickets cost$10 and youth tickets cost $7 each. How many of each kind of tickets were sold?

**College Algebra**

At 1:30 Marlon left his house to go to the beach, a distance of 9 miles. He rose his skateboard until 2:15, and then walked the rest of the way. He arrived at the beach at 3:00. Marlon's speed on his skateboard is 3 times his walking speed. Find his speed when ...

**Math**

The ice rink sold 97 tickets for the afternoon session, for a total of $765. General admission tickets cost $10 and youth tickets cost $5 each. How many of each kind of tickets were sold?

**Math**

Do you solve for y first then substitute y into 10g +6y =900. Help.

**Math **

The ice rink sold 90 tickets for the afternoon session, for a total of $700. General admission tickets cost $10 and youth tickets cost $6 each. How many of each kind of tickets were sold? College Algebra - Steve today at 6:45pm g+y = 90 10g+6y = 900 I am confused.

**Math**

At 1:30 Marlon left his house to go to the beach, a distance of 11.25 miles. He rose his skateboard until 2:15, and then walked the rest of the way. He arrived at the beach at 3:00. Marlon's speed on his skateboard 2 times his walking speed. Find his speed when ...

**Math**

Nathan has $322 worth of $11 and $13 stock shares. The number of $11 shares is seven more than twice the number of $13 shares. How many of each type of share does he have?

**College Algebra**

Cassius drives his boat upstream for 30 minutes. It takes him 15 minutes to return downstream. His speed going upstream is two miles per hour slower than his speed going down stream. Find his upstream and downstream speed.

**Math**

The walking is 5. but I can not figure the skating. Help me please.

**Math**

Thank you Ms. Sue!!!

**Math**

how many different boxes, all with whole number dimensions and a different size base will have a volume of 8 cubic feet?

**Math **

A rancher is putting a fence around a square animal pen. The perimeter of the pen is 32 feet. The fence posts will be 16 inches apart. She starts by putting 1 fence post at each corner of the pen. How many fence posts does she use altogether? My solution is 32*12=384 and 384/...

**Math**

Oh then answer should be C?

**Math**

What is the relationship between 1.0 and 0.1? A) 0.1 is 10 times as much as 1.0 B) 1.0 is 1/10 of 0.1 C) 0.1 is 1/10 of 1.0 D) 1.0 is equal to 0.1 My first elimination are c and d and I know that 0.1 is 10 times as much as 1.0. Now choice b is also true. Plz help me why should...

**Math**

Erin designs a trophy stand using one-inch cubes. The stand is shaped like a rectangular prism. How many different stands can Erin design using exactly 12 one-inch cubes? A) 8 B) 3 C) 5 D) 2 My work is 4*3*1, 12*1*1, 6*2*1, 2*2*3 Erin can make 4 different stands. Could someone...

**Science **

how many times does the sun appear to rise in a week? A) one B) Five C) seven D) not there I think it's c) seven. Plz check. Thank you!

**Math**

Lindsay draws a right triangle and adds the measure of the right angle and one acute angle. Which is a possible sum of the two angles? A) 180 B) 45 C) 90 D) 120 Answer is D) 120. Please correct me if I am wrong. Thank you for your help.

**math NEED HELP!**

Let x be the starting temperature. y=1.25x z=y-.4y=1.25x-.4(1.25x)=.75x So the final temperature is 75% of the original temperature.

**Physics**

A+B=4i+4j-k. Find the magnitude of A+B: mag(A+B)=sqrt(16+16+1)=sqrt(33). So the unit vector of A+B is (1/sqrt(33))*(4i+4j-k). A-B=2i-2j+9k. mag(A-B)=sqrt(4+4+81)=sqrt(89).The unit vector of A-B is (1/sqrt(89))*(2i-2j+9k)

**Math**

(5*2)(3*15) Thanks

**Math **

I need help to convert this expression in word problem not solution. Please help. Thanks! (5x2)x(3x15)

**Math**

Second problem I know how to solve but I have to convert this expression to word problem.

**Math **

I have done this problem converting numerical expression to word problem . Like (12x2)+(4x3) At arcade Jeff got 12 plushy for 2 coins each and 4 hand clapper for 3 coins each. Question asked how many coins he paid to buy all these toys? Answer is - 36 Now I am stuck with this ...

**Math**

I have to write a word problem with this expression. (3x2)x(3x15) Please help. Thank you!

**Math**

A chef makes 4 different quiches as the special of the day. At the end of the day, each dish had 3/8 of the quiche left. How much quiche was bought in all? Could someone please explain how to solve this problem?

**Geometry **

How to post a geometry question with picture?

**Math**

ohhh okay thank you.

**Math**

No no. I meant why did you multiply 2/3, 36/1, and 3/4?

**Math**

I get what you did, but can you please explain it to me? Sorry for the inconvenience.

**Math**

A certain grometry class has 36 students. if two-thirds are boys and three-fourths of the boys are under six feet tall, how many boys in the class are under 6 feet tall?

**math**

Thank YOU!!!

**Geometry **

Quadrilateral ABCD is a parallelogram. If adjacent angles are congruent, which statement must be true? A. Quadrilateral ABCD is a square. B. Quadrilateral ABCD is a rhombus. C. Quadrilateral ABCD is a rectangle. D. Quadrilateral ABCD is an isosceles trapezoid. My first pick is...

**Economics**

If an industry is highly profitable, new firms are likely to enter the market. This would be reflected with a shift of the A- demand curve to the right B-supply curve to the right C-supply curve to the left D- demand curve to the left

**Math**

Thank you!

**Math**

An ostrich at the zoo weighs 3 times as much as Marks's pet dog. Together, the ostrich and the dogweigh 448 pounds.how much does the ostrich weigh? Please help.

**English**

On this day, May 12, 2017, the album of the century was released: Harry Styles by Harry Styles Tracklist: 1. Meet Me In The Hallway 2. Sign of the Times 3. Carolina 4.Two Ghost 5. Sweet Creature 6.Only Angel 7. Kiwi 8.Ever Since New York 9. Woman 10.From the Dining Table You ...

**Physics**

A motorboat is headed [W35ºN] with its engine set to move the boat at 25 km/h in still water. The current is flowing at 18 km/h [S]. What is the velocity of the boat relative to the shore? My work: cos(35º)=x/25 25cos35=x x=20km/h I have an issue with finding the ...

**Math**

This is going to seem like a silly question, but I have to round points that fall on a graph to the nearest 1.25. Some of the points are 4.75, 4.5, 4.25, etc. - what would these round to? I just want to make sure I'm doing this right!

**Statistics**

What is the probability that the average lifetime of 25 bulbs would be no more than 1550 given mean of 1500 and standard deviation of 200 hours. I know that it is asking P(x less than or equal to 1550), x is 25, u equal 1500 and sd is 200. I'm having problems getting to ...

**Statistics**

What is the probability that the average lifetime of 25 bulbs would be no more than 1550 given mean of 1500 and standard deviation of 200 hours. I know that it is asking P(x less than or equal to 1550), x is 25, u equal 1500 and sd is 200. I'm having problems getting to ...

**Statistics**

Please help me understand this is asking and how to solve. P(-2>Z and Z<-1)= and X~N(3,4). Find value c such that P(c<x)=.7 Thank You!

**Texas State History**

What is the purpose of the NAFTA treaty?

**Physics**

A pilot checks her instruments and finds that her airspeed is 345 km/h and that she is heading in a direction [S40ºW]. A radio report tells her that the wind velocity is 85 km/h [NW]. What is the velocity of her plane relative to the ground? I tried to draw ...

**history**

The 60's were a tumultuous decade: which event(s). legislation, etc. do you feel has impacted or changed history the most? thank you

**Chemistry**

When 0.010 moles of Zn(s) reacts with 30.0 mL of 1.0 M HCl, the H2 gas produced is collected in a 1.0 L flask at a temperature of 270 K. What is the pressure (atm) of H2 gas collected? Zn(s) + 2HCl(aq) à\longrightarrow ZnCl2(aq) + H2(g)

**Math**

1 pt) Consider the function f(x), for which f(0)=4 and f?(0)=?6. Find h?(0) for the function h(x)=1/f(x). h?(0) =

**Math**

One hour after x milligrams of a drug are given to a person, the change in body temperature T(x) (in degrees fahrenheit) is given by the function T(x)=x^2(1âˆ’x/3). Further, the rate Tâ€²(x) at which T changes with respect to the size of the ...

**Math**

f(x)=x^9h(x) h(âˆ’1)=5 hâ€²(âˆ’1)=8 Calculate fâ€²(âˆ’1).

**Math**

Suppose that f(x)=6x^âˆ’4+9x^âˆ’2. Evaluate each of the following: f'(3)= f'(-1)

**Math**

For what values of x is the tangent line of the graph of f(x)=2x^3?12x^2+19x+0 parallel to the line y=1x+0.7 ? Enter the x values in order, smallest first, to 4 places of accuracy:

**Calcalus**

A population P is a function of time t that had 5000 when t=0 can be written P(t)= 5000+B(t)-D(t). B(t) is the number of births since t=0 and D(t0 is the number of deaths since t=0. suppose at a given instant B=800 and dB/dt=100, and D=1000 and dD/dt=85. What is P? What is dP/dt?

**history**

i was needing help on picking the answer out of those 5

**history**

For a registered political party in a statewide election to gain ballot access, it must do the following except.. - obtain 5 percent of the vote in any statewide election. - voters cannot sign multiple petitions. - collect petition signatures equal to 1 percent of the total ...

**Chemistry**

How many grams of K2SO3 would be required to react completely with 200.0 mL of 0.245 M HCl

**organic chemistry**

The constants for Antoine’s equation for TCE (based on log10 and o C) are: A= 6.5183, B = 1018.6 and C = 192.7. If a container (negligible volume) is placed in a sealed room 1000 m3 at 30 oC, how many grams of TCE will evaporate upon reaching equilibrium with the liquid ...

**Math - Algebra 1**

A field must be fenced in. There is 212 yards of fencing material to be used. What should the dimensions of the enclosed area be to ensure that is has the largest area possible? (system of equations) Dimensions_____________________

**Math - Algebra 1**

Each cow eats 4.5 cups of feed a day and the bucket it comes in contains 250 cups. The buckets cost $26.75 each. If a farm has 16 cows, how much will it cost to feed all of the cows for 1 week? (system of equations) Cost____________________

**Math - Algebra 1**

A field must be fenced in. There is 212 yards of fencing material to be used. What should the dimensions of the enclosed area be to ensure that is has the largest area possible? Dimensions_____________________

**calculus**

use implicit differentiation to show: d/dx(tan^-1x)=1/(x^2+1)

**Stats -Math**

1. We are interested in conducting a study in order to determine what percentage of voters of a state would vote for the incumbent governor. What is the minimum size sample needed to estimate the population proportion with a margin of error of 0.05 or less at 95% confidence? ...

**math**

Yes, the slope of both lines is 0.5, which means the lines really are parallel. They never intersect, so there is no point that lies on both lines, and no solution to the system.

**Physics**

A tennis ball is served from the back line of the court such that it leaves the racket 2.4 m above the ground in a horizontal direction at a speed of 22.3 m/s. (a) will the ball cross a 0.91-m-high net in front of the server? Will the ball land in the service court, which is ...

**texas history**

i need help on figuring out a topic "The topic of your report must be an issue that is being addressed by both the state and federal government"

**Physics**

Thank you so much!

**Physics**

N be going up on the knife edge with the 0.200 kg mass.

**Physics**

Would the magnitude of N also be 3.72 N?

**Physics**

A meter stick whose mass is 0.200 kg is supported at the zero cm mark by a knife edge and a force F at the 100 cm point. A mass of 700 grams is attached to the stick at 40 cm mark. Find the magnitude of N and F in Newton's.

**Math/algebra**

Thank you for helping me Ms.Sue^.^ ?^?

**Math/algebra**

Sandy drives the first 3 hours of her trip at 65 miles per hour. The last hour of the trip she drives 62 miles per hour. How far did Sandy drive on her trip?

**science**

What is the volume of chlorine that is used to produce 292 grams of hydrogen chloride?

**maths**

Calculate the lengths of the straight lines joining the following pairs of points, leaving your answers in surd form: (a) A(4,-3), B(7,6).

**maths**

The points A(1,5) and B(9,3) are part of a triangle ΔABC. The triangle has a right angle at A and and sides satisfy AB=2AC. Find a point C such that C lies above the line AB.

**maths**

Consider the 4 points A(1,5), B(-4,6), C(0,0), D(-12,12). Find the gradients of the lines: (a) AB; (b) CD; (c) BD.

**Maths**

By making the substitution u =ln x show that the following equation has exactly one real-number solution: 9/ln x + ln x^4 =-12 Sorry wrote the incorrect equation previously!

**Maths**

By making the substitution u =ln x show that the following equation has exactly one real-number solution: 9/ln x + ln x^4 =-12 Sorry wrote the incorrect equation previously!

**Maths**

By making the substitution u =ln x show that the following equation has exactly one real-number solution: -12/ln x +ln x^4 = -9

**Maths**

By making the substitution u=7^x and using part a, derive a hidden quadratic equation 7^(2x-1) +4×7^(x-1) -1/14 =0 and hence find all of the solutions to the above equation.