Friday

July 1, 2016
Total # Posts: 314

**Chemistry**

A 53.8-mg sample of sodium perchlorate contains radioactive chlorine-36 (whose atomic mass is 36.0 amu). If 29.6% of the chlorine atoms in the sample are chlorine-36 and the remainder are naturally occurring nonradioactive chlorine atoms, how many disintegrations per second ...
*June 21, 2016*

**physics**

Two identical mass-spring systems consist of 250-g masses attached to springs of spring constant 15 N/m. If one of them starts oscillating from its equilibrium position at time t = 0, how much later should the second one start so they oscillate out of phase by 90 o?
*June 9, 2016*

**Language arts**

The dragon within?
*May 24, 2016*

**math**

karen has 60 percent as much as money as leslie. leslie's sum of money is 60 %mof matthews. if matthews gives karen 140, matthew will have the same money as leslie. how much do they have altogether
*May 10, 2016*

**Math**

7/11litres of a tank is filled with water.24 litres more water are needed to fill the tank completely.What is the volume of water in the tank now?
*April 18, 2016*

**Math**

Circle the number closest in value to 4. 1. 4.123 2. 4.03 3. 3.981 4. 4.001 The answer I selected is 3.981 is this correct?
*April 10, 2016*

**math**

32/88
*March 8, 2016*

**physic**

A coconut thrown horizontally at 20 m/s from the top of a hill 63 m high. How far from the base of the hill does the coconut hit the ground?
*February 24, 2016*

**physics**

Which of the following prefixes will multiply the unit by 1,000? Select one: a. Milli b. Mega c. Kilo d. Centi
*February 24, 2016*

**math**

1.b 2.d 3.a 4.a 100%
*February 24, 2016*

**Ms. Sue, please help me on math!**

100%
*February 18, 2016*

**Math**

MATHMATHMATH What letter is in the 30th position? I think it is A but I am not sure.
*January 29, 2016*

**Math**

XYZXYZXYZ..... What is the 30th letter of the pattern I think it is Y but I am not sure.
*January 29, 2016*

**Physics**

An airplane needs to accelerate at 4.7 m/s2 to reach take-off speed before reaching the end of the runway. The mass of the airplane is 4500 kg. How much force is needed from the engines?
*January 14, 2016*

**Physics**

The brakes of an automobile are suddenly applied at the instant when its velocity is 20 m/s. If the automobile comes to a stop after 5 seconds, what is its acceleration?
*January 11, 2016*

**Math**

subtract b
*January 10, 2016*

**Math**

How would I convert 4000 cups to 400 qts?
*January 10, 2016*

**Math**

Quick question: 600 gal > 2000pt
*January 10, 2016*

**Math**

I get it now. Thanks Ms. Sue for your help. I appreciate it.
*January 10, 2016*

**Math**

How would I do 600 gal. to 2000 pt.?
*January 10, 2016*

**Math**

Is the answer .363, .333, .33, .309? Is it right.
*January 10, 2016*

**Math**

So would the answer be .363, .309, .333, and .333? Is it correct now?
*January 10, 2016*

**science**

A uniform solid sphere is placed on a smooth horizontal surface and a horizontal force F is applied on it at a distance h above the surface. The acceleration of the center?
*December 27, 2015*

**Dallas Community College**

A 2.00 kg blob of clay is moving with a velocity of 6.00 m/s at 49.0° when it collides and sticks to a 4.00 kg blob of clay that is moving with a velocity of 5.00 m/s at -123.0°. What is the magnitude and direction of the velocity of the resulting big blob of clay?
*October 28, 2015*

**maths**

33.54km
*October 28, 2015*

**Mathematics**

A bullet is found embedded in the wall of a room 2.9 m above the floor. The bullet entered the wall going upward at an angle of 36.7°. How far from the wall was the bullet fired if the gun was held 1.1 m above the floor?
*October 18, 2015*

**Physics**

Consider the equation v = (1/7)zxt2. The dimensions of the variables v, x, and t are [L/T], [L], and [T] respectively. The numerical factor 7 is dimensionless. What must be the dimensions of the variable z, such that both sides of the equation have the same dimensions?
*October 16, 2015*

**math**

Beaker A,B and C contain water with a total volume of 1 litre.Beaker B has 125 millilitres less water than beaker A. Beaker B has twice as much water than Beaker C.Find the volume of water in beaker B.
*September 3, 2015*

**Math97**

Rename as a decimal 7/8 and how do get the answer 0.875
*August 21, 2015*

**Physics**

Bill, Would you not use: M = 2x10^30 a = 0.5 AU Giving: p = sqrt(((4*pi^2)(0.5*1.49x10^11)^3)/((6.67x10^-11)(2x10^30))) = 1.106x10^7 seconds = 0.35 years Note: Bill's verison of Kepler's 3rd Law is incorrect. Where Bill said: (4pi)^2, it should be: (2pi)^2 = 4*(pi^2)
*August 14, 2015*

**mathematics**

Candice makes gift boxes during her free time.She charges 40 cents for a triangular box,50 cents for a heart shaped box and a cylindrical box for 60 cents.Last Sunday,Candice sold 16 different types of boxes and collected a total of 8 dollars.How many of each type of box did ...
*July 9, 2015*

**business math115**

CORRECTION.. .5= .75 which is the same thing as 45 minutes worked. 40x + .5x(1.5) + 9x(2) = 58.75 * 13.50 = 793.125 OR $793.13 CHECK 793.125/58.75 = 13.50
*June 24, 2015*

**business math115**

She worked 40 reg hrs, 1/2 (time and a half hrs) Time and a half 1/2 hr=30 min,, at time and a half it= 3/4 or .45 min. She also worked 9 hrs at double time-- 9*2=18 reg hrs, SO.. 18+.45+40=58.45 * 13.50 = 789.075 In Gross earnings. Rounded= $789.08
*June 24, 2015*

**LA**

yep 1.first 2boxes 2.1and3 box 3.c 4.b I got 100%
*June 3, 2015*

**Language Arts**

yep its D C A A I got 100%
*May 20, 2015*

**science (any tutor)**

100% again
*May 18, 2015*

**Social studies**

1. a 2.d 3.c i got 100%
*April 28, 2015*

**mathematics**

Tom,Jerry and Ali share 279 marbles. Tom has 4 times as many marbles as Jerry and Ali has 36 more marbles than Tom. (a)How many marbles does Jerry have? (b)How many more marbles does Tom have than Jerry?
*April 28, 2015*

**math**

Agus sold packets of sweets to Halim and Kairi in the ratio 8:13.He sold the sweets in 2-kg packets.What was the smallest possible mass of sweets Agus sold to both of them?
*April 21, 2015*

**math**

When 15 is subtracted from a number,the anwser is the same as when the number is divided by 6.
*April 17, 2015*

**math**

An architect is designing an office building with n floors that will have an FM radio antenna 15.85m tall on its roof. Each floor of the building will be 3.9m high. Which equation can be used to find the total height, h, of the building in meters, including the FM antenna? A. ...
*April 9, 2015*

**math**

Thanks!
*April 8, 2015*

**math**

To the nearest tenth, what is the distance between (7,4) and (12,5)? a) 4.8 units b) 4.9 units C) 5.0 units d) 5.1 units Please explain. Thank you.
*April 8, 2015*

**math**

Susie bought 5 kg of flour and 4 kg of sugar for $14.80.If 3/4kg of flour cost as much as 3/5kg of sugar,find the cost of 1kg of sugar.
*April 6, 2015*

**Math**

Can you please solve it for me? Im still a bit confused...
*March 30, 2015*

**Math**

In a deck of 52 cards, 3 cards are chosen. What is the probability that all three card are picture cards? (king, queen, jack) By the way, we are learning combinations and permutations. Help would be greatly appreciated!
*March 30, 2015*

**Geometry **

In a triangle, we have line QR parallel to line ST, PQ = 8, QS = 6, and PT = 12. Find PR.
*March 29, 2015*

**Math**

In triangle ABC, points X and Z are on line AB and Y is on line AC such that line XY is parallel to line BC and line ZY is parallel to line XC. If AZ = 8 and ZX = 4, then what is XB?
*March 28, 2015*

**Maths- Proof**

I understand thanks!
*March 5, 2015*

**Maths- Proof**

The question is: Prove algebraically that the difference between the squares of any two consecutive even numbers is always a multiple of 4. My working was: Let the numbers be n and n + 2 (n+2)^2 - (n)^2 =n^2 + 4n + 4 - n^2 =4n + 4 =4(n + 1) But the answers say the numbers ...
*March 5, 2015*

**algebra**

A coffee merchant sells a customer 3 lb of Hawaiian Kona at $9.75 per pound. The merchant's scale is accurate to within ±0.03 lb. By how much could the customer have been overcharged or undercharged because of possible inaccuracy in the scale? (Round your answer to ...
*February 10, 2015*

**algebra**

Mary has $4.00 in nickels, dimes, and quarters. If she has twice as many dimes as quarters and forty-seven more nickels than dimes, how many coins of each type does she have?
*February 10, 2015*

**statistics**

A company has four production sections viz., S1, S2, S3 and S4 which contribute 30%, 20%, 28% and 22% of the total output. It was observed that those sections respectively produced 1%, 2%, 3% and 4% defective units. If a unit is selected at random and found to be defective, ...
*February 4, 2015*

**Physics**

A flat disk 1.0 m in diameter is oriented so that the plane of the disk makes an angle of pi/6 radians with a uniform electric field. if the field strength is 589.0 N/C, find the electric flux through the surface. I know that Flux=(integral)|E|cos(theta)dA but I'm not sure...
*February 3, 2015*

**civil engineering **

Two masses are connected by a light cord over a frictionless pulley as shown. If M1 = 8.9 kg and M2 = 5.7 kg, calculate the tension in the cable (in N). Take the coefficient of kinetic friction between M1 and the horizontal surface to be 0.3 and assume the acceleration due to ...
*January 23, 2015*

**Physics C**

A charged particle is released from rest in a region that has a uniform electric field of magnitude 64.0 N/C. After traveling a distance of 0.500 m in this region, the particle has a kinetic energy of 0.880 J. The charge on the particle is _______ C
*January 14, 2015*

**CAL-Critical points**

For the function F(x) = inx/x^2 , find the approximate location of the critical point in the interval (0, 5).
*December 29, 2014*

**Chemistry**

Benzene, C6H6, consists of six member ring of sp2 hybridized p orbital. How many (pi)_2p bonding, anti bonding, and nonbonding molecular orbitals exist for benzene?
*December 11, 2014*

**Chemistry**

Calculate the percent purity of a sample of zinc metal if 325 mL of hydrogen gas is collected by water displacement at a temperature of 22.0 C and an atmospheric pressure of 745.0 mm Hg when 1.12 g of the sample is reacted with excess HCl: Zn + 2 HCl = H2 + ZnCl2. The vapor ...
*December 11, 2014*

**Calculus- Tangent Line- STEVE**

Yeah... my review didn't give me many other information besides this, thats why I was a bit unsure if my answer was correct.
*December 9, 2014*

**Calculus- Tangent Line**

What is the slope of the tangent line to the curve at the point (4, 0)? Okay, so I got 0.5, did I do this right?
*December 9, 2014*

**Art... check**

Which of the following is a convention Chinese artist Shen Zhou used in his brush paintings? He used only black ink to emphasize expressive brushstrokes. He painted several seated Buddha in the background. He painted flat, realistic figures to reflect strength and calmness. He...
*November 15, 2014*

**Physics**

Ohhhh, I was using the radius of the moon as the r instead of the arc length… I feel dumb haha Thank you, Greatly appreciated!!
*November 13, 2014*

**Physics**

The diameter of the Moon is 3.78x10^6m. It subtends an angle of .00982 radians at the surface of Earth. How far is the Moon from Earth? (Please explain I can't wrap my head around this question.)
*November 13, 2014*

**7th grade math**

consider the inequality 2x+3≤-3. Find the set of all integer solutions of this inequality that are also solutions of the inequality 5x-2<3. Please help I am really confuded
*October 22, 2014*

**math**

semir, sarah and sung so decided to raise money for a local homeless shelter by working in a local deli. the deli agreed to donate to the shelter a portion of the profits from each meal the three sold. semir sold 3 times as many meals as sarah. sung sold 2 more meals than ...
*October 14, 2014*

**Science/chemisty**

Explain in detail how to prepare 250. mL of a 0.125 M glucose solution. The formula for glucose is C6H12O6.
*October 13, 2014*

**Physics **

A horizontal force, F1 = 85 N, and a force, F2 = 18.4 N acting at an angle of θ to the horizontal, are applied to a block of mass m = 2.1 kg. The coefficient of kinetic friction between the block and the surface is μk = 0.2. The block is moving to the right. A. Solve...
*October 9, 2014*

**accounting**

Help
*September 23, 2014*

**Trig**

Two people decide to find the height of an obelisk. They position themselves 25 feet apart in line with, and on the same side of, the obelisk. If they find that the angles of elevation from the ground where they are standing to the top of the obelisk are 65 degrees and 44 ...
*September 10, 2014*

**Chemistry**

Fannie eats a dozen doughnuts every 36 hours. How many doughnut does she eat in a week? I used Dimensional Analysis(which isn't helping at all), but it keeps giving me weird number, like 36 over 2016 or 252 over 2016.
*September 1, 2014*

**Maths**

Thanks for all the help, really appreciate it.
*August 28, 2014*

**Maths**

A circular lily pond is surrounded by a gravel walkway that is 4 m wide. Calculate the area of the walkway if the pond is 12 m in diameter.
*August 28, 2014*

**Math**

A number whose digit in the ten billions place is 5 less than 8
*June 18, 2014*

**Math**

:'(
*May 23, 2014*

**Math**

What are the solutions of the system? y = x2 + 3x – 4 y = 2x + 2 Don't understand
*May 23, 2014*

**Chemistry**

The fluoride ion concentration in a saturated solution of magnesium fluoride, MgF2, is 2.3 10-3 M. Calculate the value for the equilibrium constant.
*May 5, 2014*

**Chemistry**

Aniline, C6H5NH2, is a weak base. If the hydroxide ion concentration of a 0.201 M solution is 9.2 10-6 M, what is the ionization constant for the base?
*May 5, 2014*

**Chemistry**

Ah got it now thank you!
*May 1, 2014*

**Chemistry**

Where does the 6.4 come from? 0.784 = 5 over x then you divide 0.784 by 5? I don't quite understand sorry!
*May 1, 2014*

**Chemistry**

Calculate the grams of NaNO3 required to produce 5L of oxygen at STP if the percent yield of the reaction is 78.4%?
*May 1, 2014*

**Chemistry**

I am very confused. I tried several practice problems and am not getting them correct.
*March 26, 2014*

**Chemistry**

What is the mass if solute dissolved in the indicated volume of each of the following solutions? (b) 4.25 L of 0.450 M KIO4g (c) 60.0 mL of 0.310 M ZnSO4g (d) 60.0 mL of 0.310 M Ni(NO3)2g
*March 26, 2014*

**Chemistry**

A hospital saline solution is analyzed to confirm its concentration. A 60.0 mL sample with a mass of 50.443 g is evaporated to dryness. (a) If the solid sodium chloride residue has a mass of 0.413 g, find the mass/mass percent concentration of the NaCl solution. % (b) Find the...
*March 26, 2014*

**Linear Algebra**

I need help please!! How many solutions does the system of equations have? 2x=-10y+6 and x+5y=3 a. one b. two c. infinitely many d. none y=4x+3 and y=4x+4 a. one b. two c. infinitely many d. none x-4y=12 and y=1/4x-3 a. one b. two c. infinitely many d. none
*March 13, 2014*

**Chemistry **

Ik this has been answered, but doesn't the copper oxide have something to do with it? And could you explain it in simpler terms? I'm just confused because you said forget the copper oxide, but your using it somehow, what puzzles me is the carbon dioxide, because the ...
*February 23, 2014*

**Science**

Copper Oxide + Carbon -> Copper + Carbon Dioxide Calculate the mass of carbon needed to obtain 63.5g of copper from 79.5g of Copper Oxide
*February 23, 2014*

**Science**

Copper Oxide + Carbon -> Copper + Carbon Dioxide Calculate the mass of carbon needed to obtain 63.5g of copper from 79.5g of Copper Oxide
*February 23, 2014*

**physics**

A 475 gram box is given a push and it then slides up and back down a ramp with a 35.0° incline. The coefficient of friction is 0.30. (a) Determine the rate of deceleration as the box slides up the ramp. (b) Determine the rate of acceleration as the box slides back down ...
*February 20, 2014*

**Physics **

Find the net force and the acceleration for the situation below. 30N 20N <---------------[ 5.1kg]---------->
*February 19, 2014*

**Chemistry**

This answer is not correct
*February 14, 2014*

**Chemistry**

A sample of oxygen gas occupies 500.0 mL at -185°C and 75.0 cmHg. Calculate the temperature in °C if the gas has a volume of 221.0 mL at a 55.0 cmHg.
*February 14, 2014*

**Chemistry**

A sample of gas has a volume of 1.30 L at STP. What is the temperature in °C if the volume is 13.0 L at 2.00 atm?
*February 14, 2014*

**chemistry**

If the surface area of a human body is 16,700 square centimeters, what is the total weight of the atmosphere on a human body expressed in pounds?
*February 13, 2014*

**chemistry**

Calculate the final Celsius temperature of sulfur dioxide if 0.500 L of the gas at 35°C and 650 mmHg is heated until the pressure reaches 742 mmHg. Assume the volume remains 0.500 L.
*February 13, 2014*

**Ap chem**

Thanks
*February 12, 2014*

**Ap chem**

Why does pf3 have dipole dipole internolecular forces? I thought it had dispersion...
*February 12, 2014*

**algebra**

Mike needs at least a 75% average to pass his math course. The class contains 5 exams that are equally weighted. If he scored a 64%, 86%, 71%, and a 90% on the first 4 exams, what score does he need on the final exam to earn at least a 75% in the class?
*February 2, 2014*

**Algebra**

Martin sold his computer and software for $900.00, receiving three times as much for the computer then the software. What was the selling price of the computer and software?
*February 2, 2014*

**Chemistry**

N2(g) + O2(g) → N2O5(g) What volume of oxygen gas reacts to yield 750.0 cm3 of N2O5? The reaction conditions are 350°C and 2.50 atm pressure. 2N2 + 5 O2 = 2N2O5 I balanced correctly. What is my next step to solve this problem. I am confused and I want to understand ...
*February 2, 2014*