Saturday

September 24, 2016
Total # Posts: 731

**Physics**

Help!! I would greatly appreciate help with this question. Consider a pulse of laser light aimed at the Moon that bounces back to Earth. The distance between Earth and the Moon is 3.84 * 108 m. Show that the round-trip time for the light is 2.56s.

*December 4, 2014*

**math**

Juan lives 2.5 miles to the park. It took him 12 minutes to ride his bike to the park. What was his average speed in miles per hour

*November 29, 2014*

**chemistry**

cal culate the ph of a mixture of 100 ml distilled water and 2 ml of 2M of NaOH

*November 29, 2014*

**chemistry**

i dont understand what i have to do for the calculation. what ive learnes is about acid and base titration . when we add a base to an acid until the equivalence point is reached which is where the moles of acid equals the moles of base ion .from my logicall thinking the ...

*November 29, 2014*

**chemistry**

titration of 50ml of 0.25ammonia with 0.5M HCL . a) find the initial PH value b) volume of HCL is required to reach the equivalent poinnt c)the ph at the equivalence point

*November 29, 2014*

**statistics**

X~Bin(400,0.01) np= 4 P(x>=4)= 1-P(Y<=3) 1-[P(X=3)+P(X=2)+P(X=1)+P(X=0)] 1- ((e^-4)*(4^3))/3! +((e^-4)*(4^2))/2! + ((e^-4)*(4^1))/1! +((e^-4)*(4^0))/0!= 1- 0.4330= 0.567

*November 2, 2014*

**Psychologic**

all of the above

*October 26, 2014*

**differential equation**

in the theory of learning the rate at which the subject is memorized is assumed to be directly proportional to the amount left to be memorized. also the rate at which the subject is forgotten is directly proportional to the amount memorized in their time t. suppose M denotes ...

*October 26, 2014*

**Statistics**

part b.) p should be 0.1915 so 19 students

*October 23, 2014*

**Statistics**

So taking note of the above corrections. **Correction part a.)** p = 0.6915 p * n = 0.6915 * 100 = 69.15 approx = 69 = 69 students passed the test **Correction part b.)** 1.59 = (X-25)/10 = 40.9 marks **Corrections part c.) = (27-25)/10 z = 0.2; Z-table(0.0793) = 0.0793

*October 23, 2014*

**Statistics**

My answer for c.) 0.4772

*October 23, 2014*

**Statistics**

My answer for b.) 5.59% = 0.0559 0.0559 ~ 0.14(frm Stand/Normal Table) 0.14 = (x-25)/(10/sqrt(100)) = 25.14 x = 25.14 marks

*October 23, 2014*

**Statistics**

My answer for a.) P(X>20) = P[(x'-u)/(sd/sqrt(n)) > (20- 25)/(10/(sqrt100) p(Z>-5) = 0.1915 1.0 - 0.1915 = 0.8085 0.8085 * 100 = 80.85 ~ 81students passed the test

*October 23, 2014*

**Statistics**

The marks of 100 students in an examination are normally distributed with mean of 25 marks and a standard deviation of 10 marks. (a) Given that the pass mark is 20, estimate the number of students who passed the examination. (b) If 5.59% of the students obtain a distinction by...

*October 23, 2014*

**Biology check my answers**

Every eukaryotic cell has genetic material, A Nucleolus , A cell membrane, Ribosomes,and a Cytoplasm. The genetic material in the cell, (the DNA) is in a chromatin which allows the DNA to then fit inside the nucleolus. The nucleolus makes ribosomal subunits in the eukaryotic ...

*October 18, 2014*

**Finance**

National Health Corporation (NHC) has a cumulative preferred stock issue outstanding, which has a stated annual dividend of $8 per share. The company has been losing money and has not paid preferred dividends for the last five years. There are $350,000 shares of preferred ...

*October 13, 2014*

**math**

your team has two x·sq-tiles, three x-tiles, and one unit tile on his desk and another person has one x·sq- tile, five x-tiles, and eight unit tiles on her desk. You decide to put all of the tiles together on one desk. What is the name for this new group of tiles?

*September 17, 2014*

**xxx**

no idea ,so pls help

*September 15, 2014*

**xxx**

If ( cos ᶿ + sin ᶿ)= ã2 cos ᶿ, show that (cos ᶿ-sin ᶿ) = ã2sin ᶿ

*September 15, 2014*

**English**

Time: Saturday, from 9 A.M. to 6 P.M. Does this sentence need the comma after Saturday?

*September 9, 2014*

**English**

Bid and buy wonderful prizes from around the world. Does this sentence need a comma?

*September 9, 2014*

**vector**

find equations for the osculating normal and rectifying planes to the curve x=3t-t^2, y=3t^2, z=3t+t^3 at point where t=1

*August 29, 2014*

**PHYSICS**

A 15g bullet is fired horizontally into a block of wood with a mass of 2.5 k and embedded in the block. Initially the block of wood hangs vertically and the impact causes the block o swing so that its center of mass rises 15cm. find the velocity of the bullet just before the ...

*August 6, 2014*

**electric circuit**

Some types of fuses used to protect electric meters have resistances of several ohms. Is this objectionable (a) in ammeter circuits and (b) in voltmeter circuits? Why?

*July 29, 2014*

**Lisa**

The square of the sum of 2x and 3y is equal to the sum of the square of y and the square root of x. Which of the following represents this statement? I got: (2x + 3y)^2 = y^2 + √x But the correct answer choice is (2x + 3y)^2 = y^2 + x^2 I don't understand how, ...

*July 15, 2014*

**Math**

Find the Exact Value of the Composition cos(arcsin(1/4))

*July 14, 2014*

**Business**

Why might a business invest in another company's stock? Explain.

*July 13, 2014*

**electric circuit**

a 12 V battery is made of 36 cells each rates at 2V and 1.5 A for a given duty cycle. what is the line current and power that may be drawn from the battery? Tnx :)

*July 12, 2014*

**electric circuit**

a 12 V battery is made of 36 cells each rates at 2V and 1.5 A for a given duty cycle. what is the line current and power that may be drawn from the battery? Tnx :)

*July 11, 2014*

**statistics**

As a marketing promotion a company is going to give the first 200 customers a coupon for a discount when they enter the store. The customer cannot scratch off the coupon until they check out. the company orders 200 coupons and 150 are for 5% off, 30 are for 10% off, 15 are for...

*July 7, 2014*

**Chemistry**

How is the atomic structure of a Copper differ from Germanium, Silicon and Gallium Arsenide ? Tnx :))

*July 4, 2014*

**Math**

Let n = c x p, where p is a prime number, and c is a composite number less than p. The number c has three unique prime factors. How many unique prime factor does n^2 have?

*July 2, 2014*

**Math**

In a hardware store the ratio of shovels to rakes is 3:5. If there are 10 more rakes than shovels, how many rakes are there in the hardware store? I know shovels = r-10 but don't know where to go from there?

*June 30, 2014*

**Science**

What is the main benefit of using scientific names instead of common names for organisms? Scientific names have been around for much longer than common names have. Scientific names give everyone a shared terminology while common names can vary around the world. ...

*April 18, 2014*

**U.S. History**

thank you

*April 12, 2014*

**U.S. History**

is it women's moral, intellectual, and physical nature?

*April 12, 2014*

**U.S. History**

I think it was supposely in the passage

*April 12, 2014*

**U.S. History**

Read this passage by Booker T.Washington: I am in favor of every measure that will give to woman, the opportunity to develop to the highest possible extent, her moral, intellectual, and physical nature so that she may make her life as useful to herself and to others as it is ...

*April 12, 2014*

**Math**

What do you mean one of those is none

*April 10, 2014*

**Social Studies**

what are the advantages of privatization of Government Owned and Controlled Companies (GOCC)in a country?

*March 11, 2014*

**Science**

so it is d right? thank you

*March 2, 2014*

**Science**

which property of nutrients shows that they are a type of matter? A. Nutrients are colorful B.Nutrients can do work C. Nutrients contain energy D. Nutrients have mass

*March 2, 2014*

**physics 2**

a certain 12v storage battery with an internal resistance of 12 ohms delivers 80 A when used to crank a gasoline engine. if the battery mass is 20 kg and it has average specific heat of 0.2 kcal/kg K. what is its rise in temperaure during 1 min of cranking the engine. assume ...

*February 20, 2014*

**Calculus**

What is the integral of [(2x-y)^2]dx?

*February 16, 2014*

**Differential Equations, Matrices**

Using the matrix [cosx -sinx] [sinx cosx] rotate the parabola y=3x^2+2 by 45 degrees. State the equation of the rotated parabola and then state the coordinates of the rotated vertex and the points (-1, 5) and (1, 5)

*February 15, 2014*

**math**

. On a spelling test Carlos had to spell 25 words. Hemultiplication sign points for every word he spelled correctly. Which equation can be used to find p, the total number of points Carlos earnedfor spelling w words correctly? A p w −. B p&...

*February 14, 2014*

**math**

9. On a spelling test Carlos had to spell 25 words. He earned 4 points for every word he spelled correctly. Which equation can be used to find p, the total number of points Carlos earnedfor spelling w words correctly? A p w −. B p ...

*February 14, 2014*

**math**

The pet shop owner told Jean to fill her new fish tank 3/4 full with water. Jean filled it 9/12 full. What fraction of the tank does Jean still need to fill?

*February 10, 2014*

**math**

Thanks everyone! I just checked teacher's newsletter. She mentioned in her newsletter that was a typo error in printed homework sheet. It is a 1/3 not 1/4. I got it now! Answer is total 10 orange button. again I really appreciate your time and help.

*February 9, 2014*

**math**

A bag of buttons contains 3 red, 4 orange, 7 green and 10 blue battens. How many orange buttons should be added so that makes up 1/4 of the total? (Remember, if you add more orange buttons, your total buttons will also increase.) Pla help due tomorrow

*February 9, 2014*

**US History**

thank you

*February 8, 2014*

**US History**

what is the significance of the internment of Japanese Americans during World War II.

*February 8, 2014*

**Statistics**

99.7

*February 2, 2014*

**English**

Ms.Sue,i answered your question so can u help me?

*January 24, 2014*

**Spanish**

Tus abuelos son alemanes tus means yours in spanish, mis means mine.

*January 24, 2014*

**Fractions**

So then 4/6 is the answer! if it is i guess thnx! Im only 8 so... its hard.

*January 24, 2014*

**Fractions**

So then how can i draw it in a picture?

*January 24, 2014*

**Fractions**

My teacher showed me in a way from like a few weeks ago. I almost don't remember. I saw from other part of my homework but they were unit fractions. The questions are high level because they are Enrich level. So its kind of hard.

*January 24, 2014*

**Fractions**

can you explain it for 3rd grade? don't understand what X is?

*January 24, 2014*

**MATH Fractions**

im confused

*January 24, 2014*

**MATH Fractions**

how can you tell if an equal share is more than one whole?

*January 24, 2014*

**math**

One week Trey rented 4 DVDs and 2 video games for $18. The next week he rented 2 DVDs and 1 video game for $9. Find the rental costs for each video game and DVD.

*January 22, 2014*

**Science**

How does gravity keep the planets in motion around a star?

*January 11, 2014*

**Math**

Alice has two part-time jobs. One job she makes 8 dollars per hour and the other she makes 12 dollars per hour. One week she made worked 30 hours and made 268 dollars. How many hours at each job?

*December 31, 2013*

**US History**

Source: "Brutus" Letter XVI April 10, 1788, "John DeWitt" Letter III Nov. 5, 1787, Anti-federalists Papers They uniformly exercise all the powers granted to them, and ninety-nine in a hundred are for grasping at more. It is this passionate thirst for power...

*December 18, 2013*

**Spanish**

Rice and black beans are staple foods. They are used when making gallo pinto, which is a breakfast dish. Casado is a meal that's served for lunch and it also includes rice and beans, but is usually served with meat and salad. Fried plantains (bananas) are also fairly ...

*December 4, 2013*

**earth**

Using conservation of energy, the following equation can be written for any satellite (or planet) "caught" in a gravitational field: (1/2)MVe^2-(GM1M2)/Re=-(GM1M2)/Rmax where Rmax is the maximum altitude of the satellite and Ve is its escape velocity. Solving for ...

*December 4, 2013*

**math**

For this question you want to find h(27), so you would substitute 27 for n, giving you: H(27)=100/9(27) H(27)=0.412 dollars

*December 4, 2013*

**calc 1**

When graphing the integral of sin(x^2) is there a way to shift the graph vertically, without just tacking "+c" on the end? If it helps, the solution to this integral is .5*sqrt(2)*sqrt(Pi)*FresnelS((sqrt(2)*x)/sqrt(Pi))

*December 2, 2013*

**genral sicence**

blue stars always have the highest surface temperatures

*December 2, 2013*

**Physics (fix)**

Adding friction to a pulley problem, regardless of if a mass in on an incline or not, will almost always increase the tension in an atwood machine- type pulley problem. This is because friction will always oppose motion, so there will be more forces working against the force ...

*December 2, 2013*

**Physics**

A trailer with a mass of 2.00x 10^3 kg is pulled by a truck with a mass of 3.00 x 10^3 kg. If the applied force is 8750 N and the frictional force exerted by the road is 2560 N, what is the acceleration of the truck and trailer?

*December 1, 2013*

**Physics**

A trailer with a mass of 2.00x 10^3 kg is pulled by a truck with a mass of 3.00 x 10^3 kg. If the applied force is 8750 N and the frictional force exerted by the road is 2560 N, what is the acceleration of the truck and trailer?

*December 1, 2013*

**physics**

Suppose that the range of output frequencies is from 47.4 Hz to 14.8 kHz for a pipe organ. Take 343 m/s for the speed of sound. (a) What is the length (in units of m) of the longest pipe open at both ends and producing sound at its fundamental frequency? (b) What is the length...

*November 22, 2013*

**science**

Oh, ok. You're right. What if the seed is a marigold? I'm working on that one. Okay, thank you again Ms. Sue.

*November 17, 2013*

**science**

How many weeks does it take for a seed to start germinating? Does it depends?

*November 17, 2013*

**science**

Thank you, Ms. Sue!

*November 17, 2013*

**science**

How many cups of water are needed for a plant to begin germinating?

*November 17, 2013*

**Science**

is it c

*October 20, 2013*

**Science**

is it b

*October 20, 2013*

**Science**

Water freezes at 0 Celisus. If a temperature drop is causing a glass of water to freeze, how would a thermometer in the water most likely change as the water freezes? A. The temperature would keep rising steadily. B. The temperature would keep falling steadily. C. The ...

*October 20, 2013*

**Science**

is it D

*October 20, 2013*

**Science**

I think it is A but I am not sure

*October 20, 2013*

**Science**

Scientific investigations involve many steps and processes. Which characteristics define a laboratory experiment? A. hypothesis, models, and calculations B. test variables, data, and uncontrolled conditions C. data, conclusions, and unregulated environment D. independent and ...

*October 20, 2013*

**Science**

Astrologers relate the location of stars and planets to events in human lives. Many years ago, people classified astrology as a science. Why do modern scientists consider astrology to be a pseudoscience A. Astrology does not involve the use of telescopes. B. Astrology does not...

*October 20, 2013*

**6th Grade Math**

18yd=54ft (3ft=1yd)

*October 5, 2013*

**Algebra**

find the value of r so that the line that passes through each pair of points has the given slope (r,4), (7,1), m=

*September 27, 2013*

**Stats/math**

The deciles of any distribution are the 10th, 20th,...90th percentiles. The first and last deciles are the 10th and 90th percentiles, respectively. What are the first and last deciles of the standard Normal distribution? HOw would i solve this? thank you sooo much!

*September 14, 2013*

**Technology**

What is a object in which the electrons at one end spin in one direction and the electrons at the other end spin in an opposite direction? A. load B. turbine C. Magnet D. Charge

*September 14, 2013*

**Science**

What is a object in which the electrons at one end spin in one direction and the electrons at the other end spin in an opposite direction? A. load B. turbine C. Magnet D. Charge

*September 12, 2013*

**Science**

What is a object in which the electrons at one end spin in one direction and the electrons at the other end spin in an opposite direction? A. load B. turbine C. Magnet D. Charge

*September 12, 2013*

**Y12 Maths A**

Suppose you had written 50 letters and addressed 50 envelopes and then inserted the letters randomly. What is the probability that exactly one letter goes to the wrong person (ii) What is the probability that each letter goes to the correct person? Justify your decision.

*August 16, 2013*

**philosphy/Critical Reasoning**

any help with evaluating an article called nightmare in Green by jarret B. Wollstein

*June 24, 2013*

**Physics**

Suppose you walk 18.0m straight west and then 25.0 m straight north. How far are you from your starting point and what is the compass direction of a line connecting your starting point to your final position>

*June 11, 2013*

**Maths A Year 12**

Four years ago, an art collector bought a painting for $32 500. He knows that this painting appreciates at 15% a year. What is this painting worth now, to the nearest $100?

*June 9, 2013*

**Maths A**

$20 000 is invested in a term deposit at 5.4% p.a. with monthly rests. What will be the value of this investment after 3 years?

*June 9, 2013*

**Maths**

Quarterly changes in population are converted to an annual change by multiplying growth factors. A growth factor = 1 + i where i is the percentage increase given in decimal form. The four quarterly increases in the number of staff employed by a particular company last year ...

*June 9, 2013*

**Maths A**

In January this year, Kathryn bought a new computer for $6000. She estimates its useful life as 5 years and its scrap value as $1500. If Kathryn uses the diminishing value method, determine the value of this computer at the end of 3 years.

*June 9, 2013*

**probability statistics**

Tall clubs international Tall clubs international has minimum height requirement for men and women. If the reqirements are changed so that the tallest 4% of men are eligible, what is the new minimum height for men?

*June 4, 2013*