# Posts by sam

Total # Posts: 5,212

**physics (mechanics)**

find the constant force necessary to accelerate a car of mass 1000kg from 15m/s to 20m/s in 10s against resistance of 270N ? pls show work (answer is 770N just in case to check)

**Physics**

use s= ut +0.5at^2 give 500 = 0(t) + 0.5 (9.8)t^2 t = 10.10s

**Pre-cal**

What is the area of triangle ABC if a = 19, b = 14, and c = 23?

**Math**

Tom has taken 3 tests with an average of 88%. However, Tom really wants an A. To get an A, he has to have an average score of 93%. What score does he need on the final test to get an A? I just don't get it. Can someone walk me through the steps to get to the answer?

**Physics**

A rock climber throws a small first aid kit to another climber who is higher up the mountain. The initial velocity of the kit is 12.8 m/s at an angle of 65.7° above the horizontal. At the instant when the kit is caught, it is traveling horizontally, so its vertical speed ...

**Physics**

a crate of weight fg is pushed by a force P on a horizontal floor. (a) the coefficient of static friction is us, and P is directed at angle theta below the horizontal. show that the minimum value of P that will move the crate is given by P=usFgsectheta / 1-ustantheta (b) find ...

**Math**

There are 40 cows and chickens in a farmyard. One quiet afternoon, Lola counted and found that there were 100 legs in all. How many cows and how many chickens are there? thx...

**Do I have enough time**

Oh yea if you have notes and know what you are going to talk about. Just go for it but make sure you get it done earlier next time

**math**

whats sets of number does the number 9/10 have?

**Science**

A storm with winds over 120/km/h that can last several weeks is a? A.Tornado B Hurricane C Jet Stream D Thunderstorm I think its hurricane am i right?

**Analytical chemistry**

The hydrogen sulfide in a 79.168 g sample of crude petroleum was removed by distillation and collected in a solution of CdCl2. The precipitated CdS was then filtered, washed and ignited to create CdSO4. Calculate the percentage of H2S in the sample if 0.122 grams of CdSO4 was ...

**math**

Mr. Dunn estimates he uses 3 gallons of gas over the course of a week. How many miles per gallon does his car get when he drives 105 miles?

**history plz help**

thanks @Reed you helped me look at the article in another perspective.

**history plz help**

I don't get what it accomplished... i have this right now The Louisiana Purchase encompassed 530,000,000 acres of territory in North America that the United States purchased from France in 1803 for $15 million.

**history plz help**

Can you guys help me get started with this, I really appreciate what your doing. @Ms. Sue @Reed

**history plz help**

During the early 1800s, the United States tried to make peace with other countries in order to grow and develop. Give an example of one of these peace efforts and briefly explain what it hoped to accomplish.

**physics**

I got 71.6*10^4?

**physics**

The speed of a space shuttle is 3.2×10^6 cm/s. Convert this into miles per hour (mph) using only 12 inches/ft, 60 seconds/min, 60 minutes/hour, and 1 inch = 2.54 cm. Factor Analysis must be used. Express your result to three significant digits and in scientific notation.

**math**

A cookie recipe calls for 3/4 of a cup of flour and makes one dozen cookies. How many cookies can you make if you have 10 cups of flour and want to use it all? I said 160 cookies. I used a proportion to solve this but is there another way to solve it?

**physics**

Dolphins can hear ultrasound with frequencies up to 280 kHz. What is the speed of sound in water if the wavelength of ultrasound with a frequency of 2.80 × 10^5 Hz is 0.510 cm? How long would it take this sound wave to travel to a dolphin 3.00 km away?

**physics**

A ship anchored at sea is rocked by waves whose crests are 21 m apart. The waves travel at 5.6 m/s. How often do the wave crests reach the ship?

**Math**

So when I do that I would have 24 4/7 divided by 4?

**Math**

Is that 24 divided by 4 when you made 23 4/7(mixed fraction) an improper fraction or is 24 just a whole number?

**Math**

Can you explain this: For my math problem 23 4/7 divided 4 it says to estimate. What do I do?

**Math**

Can you help me? My math problem is: 23 4/7 divided by 4 and it says to estimate. What do I do?

**physics**

A human ear can hear as low as 15.6 Hz. If the speed of sound in the air was measured to be 340.5 m/s, calculate the wavelength of this wave.

**physics**

For an ocean wave that has the crests 6 m apart and passing a boat every two seconds, calculate the speed of the wave.

**algebra**

Please show work* . i don't get how to do this at all only 1/3 of the university students wanted to become teachers . if 2600 didn't want to become teachers, how many university students are there?

**math**

.25 lb burger costs $2.95 .50 lb burger costs $3.90 how much does a pound of beef cost?

**Spelling**

Word for finished 3rd letter is r and the 5th letter is u

**Social Studies**

What is a group of government officials?

**math 8**

steve, thank you so much for explaining this. I get it now.

**math 8**

still having trouble getting y. why multiply top by 2. first time doing this, sorry thanks for the help

**math 8**

solve the system of equations 5x+2y=11 3x-4y=4 give answer as decimal if required. any help would be appreciated, thank you

**Science Help**

What happens to the density of the air in the balloon as it is heated?

**math**

Thank you Ms.Sue

**math**

Adding= Sum What are those kind of words for subtract divide and multiply? I am not for sure what they are called.

**World History**

Which of the following tools would NOT help a geographer to understand the ways that a country’s boundaries changed over time? A.map B.timeline C.graph D.aerial photography

**Physics II**

Assuming equal point charges, calculate the magnitude of the charge in C if the electrostatic force is great enough to support the weight of a 1.95 mg piece of tape held 1.05 cm above another?

**Physics II**

A test charge of +2 μC is placed halfway between a charge of +6 μC and another of +4 μC separated by 10 cm. What is the magnitude of the force on the test charge?

**math**

A 4ft piece of pipe needs to be divided into pieces that are 2/3ft long. How many pieces are made? How many remaining?

**Health HELP ME!!**

Thx

**engineering maths. need answer asap**

But don't you convert it into the base units?

**geometry**

we have angle ABC = angle ACB = angle DEC=angle CDE, BC = 8, and DB = 2. Find AB.

**MATHS**

108

**Physics**

During volcanic eruptions, chunks of solid rock can be blasted out of the volcano; these projectiles are called volcanic bombs. The Figure shows a cross section of Mt. Fuji, in Japan. (a) At what initial speed would a bomb have to be ejected, at angle q0 = 35° to the ...

**Physics**

9886, where does it come from? How did you get it?

**statistics**

If the mean value of the weight of a particular brand of dog food is 20.6 lb and the standard deviation is 1.3, assume a normal distribution and calculate the amount of product that falls below the lower specification value of 19.7 lb

**LA**

HELP MEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEEE

**LA**

i don't get the other comments that you posted

**LA**

In all together now Jordan uses appeals to reason to try to persuade her readers that her views are important. In a paragraph cite one example of each kind of appeal in her work. thank explain whether you find jordans appeals convincing supporting your ideas with logical ...

**Art**

Why is art fun

**Physics**

Fred and George who are identical twins, same body mass, are competing in aerial skiing. Fred hits the take off with a speed of 15.8, whereas George has a speed of 8.3. How much higher will Fred go?

**Problem Solving: Make a Table**

Water for irrigation is measured in acre-feet. One acre-foot is the volume of water that would cover one acre of land to a depth of one foot. How many acre-feet of water would it take to cover 600 acres to a depth of one inch?

**Language Arts 6A**

Which of theses is a category used in the passage to contrast falcons and hawks?

**english**

The film image thus became almost square during the early years of the talkies until the space occupied by the sound track on the film was successfully reduced. Can someone explain to me what this mean? I don't understand.

**English**

What's the answer? A?

**Spelling**

I am working on synonyms and diagraphs. I need a 7 letter word, that means finished. The third letter is r. Fifth letter is probably u.

**Chemistry**

A 38.5 mL sample of HBr is titrated with 112 mL of 1.05 mol/L KOH. The density of the HBr solution is 1.75 g/mL. Calculate the percentage by mass of the HBr in the sample. How come we don't use density*volume to find the moles of HBr?

**Chemistry**

30.0 mL of 0.0200 mol/L NaOH are added to 70.0 mL of 0.0100 mol/L HCI. Calculate the [H3O+] and [OH─] of the resulting solution My answer: [OH-] = 1.00x10^-10 M; [H3O+] = 1.00x10^-4 M Teacher's answer: [OH-] = 1.00x10^-11 M; [H3O+] = 1.00x10^-3 M Am I missing ...

**Chemistry**

50 Ltr. Of a certain liquid is confined in a piston system at the extenal pressure 100 atm this pressure suddenly released and liquid is expanded against a contant atm pressure , vol. Of liquid increases by 1 Ltr and the final pressure of the liquid is 10 atm. Find the work done.

**physics**

Conserve momentum

**Chemistry**

A piece of copper alloy with a mass of 73.0 g is heated from 23.0◦C to 44.0◦C. In the process, it absorbs 558 J of energy as heat. What is the specific heat of this copper alloy?

**Math**

Can you explain how you got that please?

**Math**

A van travels for 3 hours at an average speed of 40 mph. How much longer must the van travel at an average of 55 mph so that the average speed for the entire trip will be 50 mph?

**Algebra**

Thank you!

**Algebra**

You are choosing between two different internet providers. Company A charges $75 for installation and $42 per month. Company B charges $30 per month for installation and $45 per month. After how many months will the total costs for Internet service through the two companies be...

**Math**

Yes thank you!!!

**Math**

You are offered two different sales jobs. Job A offers an annual salary of $36,000 plus a year end bonus of 1.5% of your total sales. Job B offers an annual salary of $32,000 plus a year end bonus of 2% of your total sales. How much would you have to sell to earn the same ...

**PreCalculas**

Ok thank you i don't know what i was doing wrong

**PreCalculas**

write sqrt36*3sqrt64 using exponential notation i keep getting 24 so am i doing it wrong or is that right im confused

**Pre-Calculus**

f(x) = cos(x) on the interval [−2π, 2π] (a) Find the x-intercepts of the graph of y = f(x). (Enter your answers as a comma-separated list.) (b) Find the y-intercepts of the graph of y = f(x). (Enter your answers as a comma-separated list.) (c) Find the ...

**Chemistry**

How to find the mass of a solid formed when: 45.00ml solution of 0.003 800 mol/L lead (II) nitrate is mine dish a 30.00 mL solution of 0.08800 mol/L strontium iodide

**Chemistry**

what mass of barium carbonate will dissolve in a 2.50L solutions of 0.0500 molar sodium carbonate

**writing**

lol cheat is right

**writing**

Here is what I wrote. Both Ernesto from barrio boy and the boy in "A Day's Wait" interact with adults. Ernesto interacts with Miss Ryan, while the sick boy interacts with his father. Compare and contrast how the boys interact with the adults. Focus on how the ...

**Math**

True or false: If a is any positive real number, the graph of y=a^x will go through the point (0,1). True or false: x^3+2x^2 is an exponential equation because it contains exponents. I got true for both of them is that right?

**Algebra 2**

Find the vertex of each of the following parabolas by averaging the x intercepts. Then write each equation in graphing form. Y=x^2-14x+40

**Algebra 2**

Find the vertex of each of the following parabolas by averaging the x intercept. Then write each equation in graphing form. Y=(x-3)(x-11)

**Social Studies**

Yes.

**Social Studies, Ms. Sue, Reed, Check My Work**

@Ms. Sue, Please review my answers.

**Social Studies, Ms. Sue, Reed, Check My Work**

1. Geographers use the five themes of geography to (2 points) study world history. organize information. study world music. measure locations.• 2. People invented flat maps because globes cannot show (2 points) names of continents. shapes of continents. enough detail.&#...

**English**

Choose the sentence that is written in active voice. A. A serious accident was prevented on the highway by Roger's quick thinking. B. Roger's quick thinking prevented a serious accident on the highway. C. A serious accident was prevented on the highway. D. A serious ...

**physics**

filament lamp: cost-80p efficiency-0.2 expected life- 1000 hours compact fluorescent lamp (CFL): cost- £3.00 efficiency-0.8 expected life- 8000 hours A filament lamp with a power rating of 100 w gives 2000 units of light. what power rating would a CFL need to provide ...

**chemistry**

I have two that I can not figure out: #1: calculate the MOLALITY of 10.00 g/L of the salt, if its molar mass is 100.0 g/mol and solution density D=1.100 g/mL work: 10.00 g NaCl x (1mL/1.100g) x (1kg/1000 mL)= 0.00909 kg 100.0 g x (1 mol NaCl/58.4 g Nacl)= 1.7 mol 1.7/0.0090= ...

**Philosophy**

In this case, there is not a fallacy of relevance. While it certainly does appear to be an ad hominem attack on Wolf at first, if you look carefully, you can see that the response from World Press Review is relevant to the argument being made. A quote from the source of this ...

**Check My Work Social Studies, Ms. Sue, Reed, Please**

Is 1 to study world history, or is it to organize information, @Ms. Sue

**Check My Work Social Studies, Ms. Sue, Reed, Please**

Correction- 2. People invented flat maps because globes cannot show (2 points) names of continents. shapes of continents. enough detail.•• 5. Ocean currents follow regular patterns related to (2 points) latitude.•• volcanoes. hurricanes. longitude. 8. Which...

**Check My Work Social Studies, Ms. Sue, Reed, Please**

1. Geographers use the five themes of geography to (2 points) study world history. organize information. study world music. measure locations.• 2. People invented flat maps because globes cannot show (2 points) names of continents. shapes of continents.• enough ...

**columbia high**

160 divided by 8 is 20. There is your answer.

**Math**

Bird flies 80m east, then 60m south, then straight up In to sky for 30m. A)at this point how far is bird from his nest?

**math**

Waiting for solution

**math**

Hey pls pls solve it for me.

**math**

A fruit seller buys 100 bananas for Rs 40. Twenty bananas are spoiled and thrown away. At what rate should he sell the remaining so as to gain 10% ? Pls give me the solution of it.

**math**

Thnx

**Geometry**

for the second question it is (0,0)

**math**

Sara estimated 23 x 43 using 20 x 40. Sam estimated 23 x 43 using 25 x 40. Will Sara's or Sam's method give an estimate closer to the exact answer?Explain.

**math**

A golf practice range has 245 balls. The owner bought a carton of golf balls.How many golf balls does the owner have after buying the carton? Golf Balls 12 balls to a box 15 boxes to a carate 5 crates to a carton pls help by explaining me Thank you

**Social Studies (Ms. Sue) Please Proofread**

Thank you, they were correct!

**Social Studies (Ms. Sue) Please Proofread**

1. Population density is the number of people that live in a region divided by the number of (1 point) roads. square miles or kilometers in the region.•• waterways. people who used to live there. 2. How do demographers figure out population growth? (1 point) by ...