# Posts by jacky

Total # Posts: 87

Math, calculus III
A particle moves along the path from the origin to (0, 2, 1) to (1, 2, 1) to (1, 0, 0) and back to the origin under the influence of the force field F = z2i + 2xyj+ 4y2k. Calculate the work done by direct calculation and by using Stokes’ Theorem

Math, calculus III
A fluid has constant density ? and velocity v = zi + (y2 + 2y)j ? 2xk. (a) Calculate the particle paths (field-lines). (b) Calculate the mass flux through the boundary of the region x2 + y2 ? 4 and 0 ? z ? (4?y) by direct calculation and by using the Divergence Theorem.

math algebra
Gray Glaze requires 15 hours to put a new roof on a house. His apprentice, Anna Gandy, can record the house by herself in 20 hours. After working alone on a roof for 6 hours, Gary leaves for another job. Anna takes over and completes the job. How long does it take Anna to ...

Social groups
How do virtual groups differ from in -person primary and secondary groups? What qualities do virtual and in-person groups share? I understand people join primary groups to satisfy their personal needs of belonging and fulfillment. Could the differences here is lack of face to ...

Math (Assignment due today)
Assume 11 males audition, one of them being Winston, 4 females audition, one of them being Jackie, and 5 children audition. The casting director has 3 male roles available, 1 female role available, and 2 child roles available. (1)How many different ways can these roles be ...

life orientation
identify 3 human rights violations

physics
oitt buat itaaleem kerrrr???

Science
Which of the following is not an atom found in household bleach (Na0CL)? 1) Sodium (Na) 2) Chlorine (Cl) 3) Hydrogen (H) 4) Oxygen (O) My answer it's 4 correct me

Science
Which of the following is pure substance? Chocolates milk Orange juice Seawater Hydrogen peroxide I'm not sure what's the right answer!!

Identify the independent clause in the following sentence. Before electric lighting was invented, people used candles to light their homes at night. a. Before electric lighting was invented b. people used c. people used candles to light their homes at night•• d. to ...

chemistry

chemistry

english
Ms. Sue

english

english
In this discussion, you will post issues related to motivation and learning. Refer to the texts in this section, other texts you have read, and your personal experience and knowledge to support your ideas. Begin your discussion by addressing the following questions: What are ...

geometry honors
Can you prove ABCD is a parallelogram based on the given information? Explain. Given: x = 5, y = 4 Prove: ABCD is a parallelogram. The image consists of a quadrilatera ABCD with their sides AB, BC, CD, DA as 3x + 12, 7y - 8, 6x - 3 and 5y respectively.

algebra 1
Which of the following points are solutions to the system of inequalities shown below? Check all that apply. y>4x + 2 y<4x + 5 A. (4, 21) B. (5, 24) C. (5, 26) D. (-4, 20)

math
We did not find results for: a conical tank with its vertex down is 12 feet high and 12 feet in diameter at the top. water is being pumped in at the rate of 8 feet cubed per minute. find the rate at which the water level is rising when the water is 4 feet deep.

world history
was antonio da sangallo poor or wealthy

Problem solving
l pay 900.00 rent for 31 days, l moved in on 13 of august and moving out on 4;th september. how much would l get for 9 days from my landlord. thanks jacky.

Science
Does ΔT from evaportation increase or decrease with increasing molecular mass? Explain why?

Science
Predict change in temperature for 1-butanol, CHSCH2CH2CH2OH, if same experiment were using 1-butanol?

Science
Using concept of Surface Tension, explain why does the detergent cause the effect observed?

Science
Explain why pentane has a significantly higher vapor pressure than 1-butanol?

engineering
In a Direct Shear Test please help. 1)How do we determine the spacing between the two parts of shear box? What would happen if it is not set properly? 2) The shear and normal stress can be calculated with the corrected area considering the movement of displacement. How would ...

STAT
Suppose adults in a particular town drive a mean of 65 mph with a standard deviation of 15 mph. Using the normal curve table, a.What percentage of adults drive below 35 mph? b.What percentage of adults drive below 68 mph or above 85 mph? c.What percentage of adults drive ...

STAT
Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : µ = 700 Research Hypothesis H1 : µ ≠ 700 •What is the test statistics? •At a 0.05 ...

STAT
Thanks Reiny. That really help.

STAT
The weights of the 100 students in an introductory statistics class are normally distributed, with a mean of 170 pounds and a standard deviation of 5 pounds. How many students would you expect to have weight between 162 pounds and 178 pounds? What is the probability that a ...

STAT
A researcher is examining the relationship between color preference and gender. A sample of 30 men and 30 women is obtained and each person is asked to identify his/her preference between two choices of paint colors for a new student lunge. For this sample, 5 of the men ...

STAT
Thanks that help a lot. Jacky

STAT
The Cox family has 4 boys. •What is the probability of a 4-child family having 4 boys? •What is the probability that the next child of the Cox family will be a boy, given that they have already 4 boys in a row?

STAT
The weights of the 100 students in an introductory statistics class are normally distributed, with a mean of 170 pounds and a standard deviation of 5 pounds. 1)How many students would you expect to have weight between 162 pounds and 178 pounds? 2)What is the probability that a...

STAT
The weights of the 100 students in an introductory statistics class are normally distributed, with a mean of 170 pounds and a standard deviation of 5 pounds. How many students would you expect to have weight between 162 pounds and 178 pounds?

STAT
A certain personality index postulated by Professor Bailey is normally distributed, with a mean of 0.4 and a variance of 0.0004. What is the probability that the Professor Bailey’s personality index of a randomly selected person will exceed 0.44?

STAT
The score on a test are normally distributed with a mean of 75 and a standard deviation of 6. If the professor wishes to give A’s to the top 4%, what would be the cutoff score be for A’s?

STAT
Thanks, Jacky

STAT
Assume that women’s heights are normally distributed with a mean given by µ = 64.6 inches and standard deviation given by σ = 2.2 inches. What area under the normal curve corresponds to the probability that a woman’s height is between 63.7 inches and 64.7 ...

STAT
Lucinda used ANOVA to test if there were statistically significant differences between the five conditions of her independent variable. There were 8 participants in each condition. Her obtained F-test (df between = 4, df within = 30) was F = 10.897/3.72 = 2.914, p < .05. ...

STAT
Given a sample size of 18, with sample mean 660.3 and sample standard deviation 95.9, we are to perform the following hypothesis testing: Null Hypothesis H0 : µ = 700 Research Hypothesis H1 : µ ≠ 700 •What is the test statistics? •At a 0.05 ...

Physics
The mass of a certain neutron star is 1 × 1031 kg (5 solar masses) and its radius is 5500 m. What is the acceleration of gravity at the surface of this condensed, burned-out star? The value of the universal gravitational con- stant is 6.67 × 10−11 N · ...

Physics
Find the magnitude of the gravitational force a 65.4 kg person would experience while standing on the surface of Earth with a mass of 5.98 × 1024 kg and a radius of 6.37 × 106 m. The universal gravitational constant is 6.673 × 10−11 N · m2/kg2. ...

Physics
A bicyclist is riding at a tangential speed of 13.9 m/s around a circular track with a radius of 38.4 m. If the magnitude of the force that maintains the bike’s circular motion is 378 N, what is the combined mass of the bicycle and rider? Answer in units of kg

Physics
A ball is thrown vertically upward with a speed of 26.1 m/s from a height of 2.1 m.How long does it take to reach its highest point? The acceleration of gravity is 9.81 m/s2. Answer in units of s

Physics
Sally travels by car from one city to another. She drives for 36.5 min at 90.7 km/h, 13.3 min at 120 km/h, and 57.4 min at 45.6 km/h, and she spends 16.3 min eating lunch and buying gas. Find the total distance traveled. Answer in units of km

physics
The Earth’s radius is about 6380 km. The space shuttle is orbiting about 275.0 km above Earth’s surface. If the average speed of the space shuttle is 23500 km/h, find the time required for it to circle Earth.

economic
explain the importance of the following terms in the u.s. free enterprise systerm;(A) profit motive, (B) voluntary extange, (C) private property rights, and (D) compition

senn high school
Write a 1-2 paragraph on a topic of your choice using at least 3 of the figurative language we have reviewed so far.After your paragraph ,list the types of figurative language you used ?

senn high school
Please wite a paragraph (5sentences)to show you comprehend what analogies and idioms are.Use at least one analogy and one idiom in the paragraph?

finance
indexing exemption for inflation. each year, the internal revenue service adjusts the value of an exemption based on inflation ( and rounded to the nearest \$50.00). in a recent year, if the exemption was worth 3,100 and inflation was 4.7 percent, what would be the amount of ...

phsyics
A brick of mass 1.5 kg slides down an icy roof inclined at 30.0° with respect to the horizontal. (a) If the brick starts from rest, how fast is it moving when it reaches the edge of the roof 1.75 m away? Ignore friction. m/s ? (b) Redo part (a) if the coefficient of ...

physics
Thank you so much! :)

physics
A cart starts from position 4 (which is 20m above ground) in the figure below with a velocity of 11 m/s to the left. Find the speed with which the cart reaches positions 1, 2, and 3. Neglect friction. speed at position 1 m/s? speed at position 2 m/s? speed at position 3 m/s? ...

math
standard form numbers are used around the world for....... 1:speed of light i need 3 more situations when you use standard form

physics
A roller coaster has a loop the loop with a loop radius of 14.5 m. What is the minimum speed that the cart must have so that unconstrained riders do not fall out when the cart is upside down at the top of the loop? What condition on the riders is met at this speed?

algebra
the perimeter P of a square is four times the length of ones side s, or P=4s. Is (1455) a solution of this equation? If not, find a solution that uses one of the given values

!!MATH!!
A decroative floor pattern has one red square tile surrounded by 12 blue tiles. Write and evaluate an expression to show how many total tiles (red and blue) are needed if there are 15 red tiles. Then make a table showing the total number of tiles if there are 15,20,25, or 30 ...

math
OMG I STILL DON'T UNDERSTAND THT! i have to know how to do it

Ap Chemistry
E = hc/? where h = 6.626 E -34 Js +2.914*10^(-18) J = [6.626*10^(-34) Js (3*10^8) m/s] / ? so do some mathematical manipulation and isolate ? to get: ? = [6.626*10^(-34) Js (3*10^8) m/s] / +2.914*10^(-18) J & you can use a calculator to get the final answer :)

How to do a standard form?

Life orientation
Department of environmental affairs

Chemistry
Need Help On This Question.! Potassium chloride reacts with bromine forming potassium bromide plus chlorine. If 500g of potassium bromide are produced, how many grams of potassium chloride reacted?

Pre Calc
Solve for x: |4x+6|-|2x-1|<5

math
6x (squared) = 23x+18 help please

chemistry
how many moles of acid must be added to the blood to bring the carbonic acid/hydrogen carbonate ratio from 1:2 to 1:10?

government
Which statement about the senate is true?

chem
What volumes of 0.53 M HNO2 and 0.46 M NaNO2 must be mixed to prepare 1.00 L of a solution buffered at pH = 3.55? HNO2

chemistry
You have a sample of magnesium chloride. If there are 3.90 mol of Cl, how many moles of magnesium atoms are there?

high school math
what is (1+2y)(3+5y)

pennies are kept in a jar the mass of the jar is 20 g the mass of each panny is 5g le t the varible p represent the total mass of pennis and the jar. let the variable n represent the number og pennys. 1a. write an equation that represent the relation ship between mass p and n ...

the surface of our earth is 20'c for every km, k below the surface the tempature increses by 10'c. let t represent the tempature in 'c 1a write an equation that represent the relationship between disatnce k and t tempature 1b. what is the slope and and y-intercept

im learnin about y=mx+b 1.describe the line you think each equation represent Y=x, y=5, x=-3 2. The equation of a line is y=mx+2. determione the value of m when the line passes through each point D(12.5) s(1.-3) e(-2.6) a(-5.1)

math
the serface of our earth is 20'c for every km, k below the surface the tempature increses by 10'c. let t represent the tempature in 'c 1a write an equation that represent the relationship between disatnce k and t tempature 1b. what is the slope and and y-intercept

PHYSICSS!!!!!
At t = 0, a particle moving in the xy plane with constant acceleration has a velocity of vi = (3.00 i - 2.00 j) m/s and is at the origin. At t = 2.00 s, the particle's velocity is v = (6.60 i + 4.00 j) m/s. Find the acceleration of the particle at any time t. (Use t, i, ...

P1=(-3,2);P2=(-6,-2)

Mr. S, a dealer of musical instruments, persuades me to buy an electronic organ, orally promissing that I can return the organ if I cannot learn how to play it. I signs a standard written form contract, which does not include this provision. I will not be able to testify as to...

Electrons circuits
I am sorry for my unclear explanation. Actually the monitor is powered by a 9V 100mA adaptor. I am not sure if the voltage drop across the speaker is AC or DC because the voltage keep changing from 0.9V to 1.5V on my voltmeter. Current is around 3.8mA. The microcontroller is ...

Electrons circuits
Hi everyone! I'm new in here. Recently I bought a movement monitor which detects micro movement. If the sensor does not detect a movement in 20 seconds, the build-in speaker will beep until the sensor detects a movement. I'm using it for my project and I have a ...

math, basic
how do you write 5 and a half in a fraction not like this because i thought it was 5 1/2 but it was wrong. 5 1/2 is also 11/2, which is considered an improper fraction. I hope this is what you were asking.

math,help
I definately do not understand this problem. If y varies directly with x, and y = 600 when x = 1000, find the constant of variation K. If y is directonally (proportional) to x, then for every value of x there is a value for y multiplied by a constant value. So if was that we ...

math,help
What is the equation i have to use for the following question A roof rises 9.75 ft over a horizontal distance of 15.84ft. What is the slope of the roof to the nearest hundredth? Slope is given by slope=rise/run So what is the rise and what is the run?

math help & correction
Problem #1 Is this correct or wrong? Find the slope of the line passing through the points(-1, -1)and(-1, 2). Write the equation of the line. For this one I KEEP GETTING Y= - (3)/(2)x-2.5 Problem #2 Find the y-intecept and slope of 7x+9y=72 My answer: Slope is: - (9)/(8) y-...

math,algebra
can someone help me i've tried different numbers but i can come out to factor this: 2b^2+6b-216=0 why don't you divide the equation by 2 to get b^2+3b-108=0 now by trial and error, can you find two factors of 108 that have a difference of 3? (b-9)(2b+24)

math,help
Can someone help me understand the following in terms that i can understand because i've read the book,definitions i've done research and i am new with this and i still don't understand.The teacher is hopeless at explaining that's why i am here for help. 1) ...

Unscrambling
reatstuec in French (begins with les) Thank you for using the Jiskha Homework Help Forum. Sorry but it's too late this evening for me to even think. Usually an exercise like this would use the vocabulary you have been studying. Without knowing your textbook and the chapter...

unscrambling a French word associated with art
unscramble tertcueas (it's in french and the beginning is les...) This might work: http://www.ssynth.co.uk/~gay/anagram.html Be sure to click the circle by "French," and be sure to uncheck the box before "Include single-character words (a and I)"...

lauguage arts
what do rats do I need help fast. It looks as if what you need to do is learn how to conduct thorough and effective searches for yourself. That's what research is, and I'm sure that's what your teacher expects you to do -- conduct research. http://www.sou.edu/...