# Posts by mark

Total # Posts: 1,728

Math
Oh sorry 246 marables

Math
Liz, jas and Sam each have a collection of marbles. The three of them pool their marbles to make a larger collection. They weigh the marbles on a postal scale. Together they have 2\$6 marbles which.weigh 183 ounces. What is the average weight(unit rate) of each marble?

physics
Thanks

physics
A storage tank at stp contains 18.5kg of nitrogen. What is the volume of the tank and what would the pressure be if you added another 15kg of nitrogen at the same temperature?

physic
c) Given these views of Darwin, we can derive an expectation of the ratio of transitional to non-transitional fossils found. I include in the following only those factors which yield a differential expectation of discovery of transitional fossils displaying the action of ...

physic
Given these views of Darwin, we can derive an expectation of the ratio of transitional to non-transitional fossils found. I include in the following only those factors which yield a differential expectation of discovery of transitional fossils displaying the action of natural ...

English - Native speakers
Ok and the last one. Is there a singular form of sheets? Do we say change your sheets? (sheets on the bed, not a sheet of paper)

English - Native speakers
Can we then say He may have come yesterday or just He might have come yesterday? Can we use may in the past tense or not?

English - Native speakers
Ok thank you both :) One more question. Is might the past form of may?

English - Native speakers
Yes thank you and is there a singular a toiletry or just plural toiletries?

English - Native speakers
Hello! What does toiletries mean? Is this stuff we use in our bathroom e.g. toothbrush, comb etc. or is this a perfume but with higher percentage of water?

English - Native speakers
Hello what is the difference between a supermarket and a market a chemist and a pharmacy a shopping centre and a department store a shopping centre and a shopping mall

Calc
[9:52:53 PM] Pardeep Narang: y''+2ty'−4y=8 y(0)=4 y'(0)=0 i need to solve this using laplace transforms

geometry
in a regular polygon, with center O, and a side AB, measure of angle AOB =72 degrees. If AB is 4.6 in. find the perimeter

physics
Thanks, very much.

physics
The gauge pressure in each of 4 car tires is 240kpa. If each tire has a footprint of 220cm^2 , what is the mass of the car?

Physics
A raindrop (mass 1.00 g) is travelling at a speed of 40m/s when it hits the surface of 100 g of water contained in a drinking glass. What is the change in temperature of the water in the glass if we assume that a) all the kinetic energy of the raindrop is converted to energy ...

anatomy
Compare and contrast the two feedback mechanisms our bodies use to maintain homeostasis what would happen if our thermoregulation used positive feedback to maintain homeostasis

English - Native speakers
Ok I got confused How to solve the following example? My brother__ wife__ name is Pauline. Where do we put possessive s???

English - Native speakers
Helo :) Can you tell me if the following explanation of mine concerning possessive s is correct? We put 's with every noun in singular (my mother's house)and when we have irregular plurals (this is my children's school) We put just the apostrophe when we have ...

English - Native speakers
Another one! Why can't we say this stain remover is very efficient. Why do we say effective? What is the difference? What are facilities and what amenities? When do we use specimen and when sample?

English - Native speakers
Hello what is the difference between a chef and a cook? Another question: If we have a sentence: It is mary's and john's birthday today do we put apostrophe where I put it? Can we say: He said in he camera or he said to the camera? (On TV) Do we say he lied on the bed ...

Chemistry
Thanks!

Chemistry
Vinegar is a dilute solution of acetic acid. In the titration of 5.00 mL of vinegar, 39.75 mL of 0.137 M sodium hydroxide solution was required to neutralize the vinegar to a phenolphthalein end point. Calculate each of the following of the vinegar. (a) the molarity : I got 1....

Chemistry
A 22.3 mL sample of a weak monoprotic acid, HX, requires 50.0 mL of 0.040 M NaOH to reach the equivalence point. After the addition of 30.0 mL of NaOH, the pH is 5.30. What is the Ka of HX?

physics
Thanks , I knew this just didn't seem right.

physics
A 33kg traffic light hangs from a vertical beam by two wires. The wire on the left side of the light has an angle of 53 degrees to the beam and the right side wire has an angle of 37 degrees with the beam. Calculate the tension in each of the wires. Would the tension just be ...

math
Chords AC and BD intersect at the center of circle ABCD. If the length of CP = 8, which is the length of PB?

English - Native speakers
Hello! How do you call a person who checks if passengers in buses or trains have tickets? It is not a conductor right? Conductor is a person who conducts an orchestra. Another question: How do you call the woman who is helping a woman to give birth? and do you say indefinite ...

math
3 1/5 x 2 5/6 express in simplest form

English - Native speakers
So you don't write :I live in the North?

English - Native speakers
Do you write North South East West with a capital letter? Why do you write then: He lives in north London?

physics
A merry-go-round of mass 1640kg has a radius of 7.5m. How much work is required to accelerate it from rest to a rotation rate of 1 rev. per 8 seconds? (assume a solid cylinder) /

English - Native speakers

English - Native speakers
I have couple more sentences: when we heard unusually dog barking. Can we better say when we heard unusual dog barking or unusual barking of a dog. do we say the dog was barking crazy or like a crazy? He was trying to explain us something or to us something? car was empty of ...

English - Native speakers
How would you correct this sentences? It should have been a day just like other days.A usual day

English - Native speakers
Thank you :)

English - Native speakers
Hello! Can we say: Are you going to apply to a job soon? or is apply for a job more correct? In which cases can we say apply to?

physics
A 650g ball on the end of a light rod is rotated in a horizontal circle of 1.2m radius.Calculate the torque needed to keep the ball rotating if the air resistance exerts a force of .02N on the ball. Ignore the moment of inertia and the air resistance of the rod.

Yes , but 39s

Multiply the # outside the parenthesis by each item inside the parenthesis to remove the parentesis and then combine the like terms (r's & s's).

English - Native speakers
Hello! Is it correct to say He watches sport on TV or he watches sports on TV. What is the difference?

physics
How can I convert 0.06981 radians/ sec^2 to rpm?

science
Magnetic field?

physics
A centrifuge takes 1 minute to turn through 20 complete revolutions before reaching it's final speed. What is the angular acceleration (assumed constant) and what was it's final angular speed in rpm? How do I solve this without knowing the radius of the centrifuge?

English - Fools Crow
Yes you did :) I just wasn't sure what exactly is the plural. I knew the singular was A French :) Thank you and I'll be back :)

English - Fools Crow
It is not an error since it is used 5 times. But it is probably your above explanation! So is the group which is learning English from the beginning now at the first degree or class or level? What is correct? I have another question. Is the plural from a French the French or ...

English - Fools Crow
This example We're in Class 2 is written in the student's book (english as a foreign language- elementary level) It is used as an example of the Present Simple Tense. So how to explain this word? It is obviously not the classroom. Could it be for example Class 1, Class...

English - Fools Crow
Oh interesting! But when this word refers to classroom, to pupils what's the explanation then?

English - Native speakers
Sorry the wrong title!

English - Fools Crow
Hello! Can someone explain to me the following sentence: We're in Class 2. Why do we write C with a capital letter? It is not classroom what is it then?

Chem
Some ethylene glycol, HOCH2CH2OH, is added to your car's cooling system along with 4.4 kg of water. If the freezing point of the water-glycol solution is -15.0°C, how many grams of HOCH2CH2OH must have been added? I used the equation: 15 celcius = 1 x 1.86 celcius/...

PHYSICS
2 pool balls of equal mass experience a perfectly elastic head on collision. 1 ball is traveling at 2m/s and the other at 3m/s in the opposite direction.What is thier speed just after impact? I know the balls swap speed and change direction but can't find the correct ...

English - Native speakers
Thank you! All clear now!

English - Native speakers
Thank you for all your help till now! Another questions: Can you please paraphrase the following sentence because I just don't get the meaning of it: In the same interview, she cited her lifelong acquaintance with fear as the reason for her relative fearlessness in ...

Math

Math
Is this right? Choose an appropriate metric unit of mass or capacity. A telephone-kilograms A single piece of paper-grams Lake Erie-kiloliters a bucket of water-liters

English - Native speakers
Another one! Why is this sentence nor correct? According to the weather, we'll either go out or stay in.

English - Native speakers
and to have on show means what?

English - Native speakers
Thank you :) It's a lot easier now! Can you help me something else? What does this mean: Women usually ask what colour the car is-men ask what make it is. What does make mean?

English - Native speakers
Hello! I am trying to figure out one of the most difficult thing in English - articles. So I have one question: Do we say I'm leaving home (Would people know that home means the place where we live?) Or is it correct I'm leaving the home? I personally think that the ...

statistics
Data shows that 93% of the people in a certain population are right-handed. A group of 9 people from this population are selected at random. What is the probability that exactly 7 of the people in the group are right-handed? 2

Math
Would it be half of 2190?

Math
No I am taking it is two

Math
Suppose Kalvin flipped a coin to determine his breakfast cereal every day starting on his 12th birthday and continuing until his 18th birthday. How many times would you expect him to eat Cocoablast cereal. I know 6 years times 365 days is 2190 what do I do next

physics
A ball is dropped from 1.5m and bounces back up 1.2m. How many times will the ball bounce before it loses 90% of its energy? I figued since the ball bouced .8 times the original hight and 10% of 1.5m is .15m that that when the bounce hight reached.15m that 90% of the energy (...

physics
A ball is dropped from 1.5 m and rebounds to 1.2m. How many times will it bounce before losing 90% of it's energy? I assumed energy was hight times gravity so when the rebound was only 10% of the original amount, 90% of the energy is lost. Is this the correct idea? I ...

physics
Thanks

physics
Two pool balls of equall mass have a perfectly elastic headon collision.The fist ball is traveling at 2m/s and the second at 3m/s in the opposite direction.what are thier speeds immediately after impact? I'm lost on what equation to use here. Does the faster velocity ...

calculus
if f'(x)=2f(x) and f(2)=1, then f(x)= ?

calculus
if dy/dx=ycos x and y=3 when x=0, then y= ?

physics
I think the force of gravity is the only force at work so what is the force of gravity in newtons?

physics
Thanks

physics
A boy sitting in a boat at rest throws a 6.4kg object horizontally out of the boat at 10.0 m/s. The mass of the boy is 26kg and the mass of the boat is 45kg. Calculate the velocity of the boat just after the package is thrown. I used momentum before = momentum after. 6.4kg*10....

English - Native speakers
Thank you! I got it. It's a bit easier now

English - Native speakers
Need some explanations about the articles! Why do we say I love Italian food and not the Italian food Why do we say I leave home at 3 and not I leave the home why do we say I go to bed at 11 and not I go to the bed at 11

English
Oh and is there some other word for an argument? f.e. What are your arguments?

English
Hello! Can you write the word Goodbye like this and like this Good bye? What about Goodnight or Good night?

physics
If an elevator with mass of 4850kg is designed to have a maximum acceleration of .068g (g is gravity acceleration). What are the maximum and minimum forces the motor should exert?

English - Native speakers
and if these words are new words for people than I should write them without articles? When I write verbs I write them like f.e. to increase to explain etc. so that is why I am asking about the nouns

English - Native speakers
Hello! When you are writing the unknown words f.e. on the board can you write the following or is something else correct (I am referring to articles): an aim- a counter-revolution- a supporter- a square- a mayor- a green area- a pedestrian zone- So should you write the unknown...

math
For how many two digit prime numbers is the sum of its digits 8

physics
Thanks , alot!

physics
A 88g arrow is shot from a bow whose string exerts an average force of 110n on the arrow over a distance of 78cm.What is the speed of the arrow as it leaves the string?

physics
Suppose you notice 6.3 ocean waves pass by a buoy in 26.3 seconds. What is the frequency of the ocean waves?

English - Native speakers
And one more thing how come is it possible to say My family are from Rome?

English - Native speakers
Hello! Why don't we say possessive pronouns in English for the following words: my, your, his, her, its, our, your, their. Why do we say possessive adjectives? It doesn't make sense to me since my mother tongue is not English. Can you maybe explain this to me? Thank you

Trig
If the terminal side of theta in standard position contains the point (5,8). Find the exact value of tan of theta

Trig
Given that theta is a quadrant 3 angle with cos of theta=-7radical65/65, determine tan of theta

English - Native speakers
Ok one more thing about quantifiers :D Can you help me and tell me which of the following sentences are correct in both ways: 1.I have no/I don't have any time - is both possible? 2.He works a lot/much 3.There are too much or to many people? I think 1 and 2 can go both way...

English - Native speakers
Thank you Writeacher for your answers today :) Here are some other questions :) : Do you say We've had a lot of rain recently or lots of rain? Can someone explain the difference between those two phrases - in your own words. Also what exactly is the difference between a ...

English - Native speakers
Ok but what about the phrase to hold the grudge against someone? For example don't hold the grudge against me but I think you are wrong Or Don't hold it against me but I think you are wrong Is this correct?

English - Native speakers
Hello! Which expression do you use the most in English? Don't take amiss to me or something similar? I am looking for a verb but I can't seem to find it in English. Is there also an expression like to take harm on someone? I hope you get the idea which verb or ...

PHYSICS
The hydraulic gradient in an 10-ft-thick aquifer at a site of uniform flow prior to pumping is -0.02. The hydraulic conductivity is 100 ft/day. True or False: After pumping starts at a well at a rate of 10,000 cubic feet per day, the distance from the well to a point of ...

In the video game Corporate Cowboy, your task is to investigate complaints of wrongdoing on the part of corporate directors and officers, decide whether there is a violation of the law, and deal with the wrongdoers accordingly. Jane, a shareholder of Goodly Corporation, ...

English - Native speakers
Hello once again! Can you tell me the difference between Don't underestimate me! and Don't underrate me! Which one is more used in English and what's the difference between those two words? Is there any other similar word? My second question. Can we say both I'...

English
Hello! I am trying to formulate the following sentence correctly: 1. "I plan to continue my education on the graduate study program of the same university." Any better ideas?

physics
If a 9800kg train car traveling at 15m/s impacts another train car at rest and after the impact the 2 are going 6m/s. What is the mass of the second train car?

Math
I think in simple terms you are removing the parenthesis, so you need to multiply 4 by each one inside the parenthesis, 4x9=36, and 4x-m=-4m so I believe tat "D" sis the answer.

calculus
Find the volume of the solid whose base is the region bounded between the curve y=sec x and the x-axis from x=pi/4 to x=pi/3 and whose cross sections taken perpendicular to the x-axis are squares.