Posts by Lenny

Total # Posts: 78

Physics
Dean is hunting in the Northwest Territory at a location where the earth's magnetic field is 7.0x 10^-5 T. He shoots at a duck decoy by mistake, and the rubber bullet he is using acquires a charge of 2.0 x 10 ^ -12 C as it leaves his gun at 300m/s, perpendicular to the ...

chemestry
what causes #catrax???.....it an eye diseses which causes a suffering petient blindness for sometimes in which the patient have head pain the blindness occars now i wan know what causes it n how it should be treated??

social studies
what can be that it's old and it's new at the same time??

Physics
A ball (mass of 0.5kg) is suspended on a string that is attached to the ceiling. The ball is charged with an unknown charge q. Determine the magnitude of the charge on the ball if the electric field strength is 2000N/C, and the string forms an angle of ? = 30°

ph
An electron is located within an electric field, with a strength of 800N/C. What is the magnitude of the force on the electron?

Physics
A ferry-boat is rectangular in shape, with an overall area of 30.0 m2. When the boat is loaded with gravel, it sinks to a depth of 2.8 m in the water. What is the total weight of the boat + gravel? Show your work.

Physics
If you suspend a 90-N rock beneath the surface of ethanol, the tension required to support it is only 60 N. What volume of ethanol (density of 789.2kg/cubic meter) must therefore be displaced? Show your work.

Physics
Explain in detail how you would find the density of an unknown high-density object if you had only the objects listed below.If you show calculations, make sure you define your variables.Assume all containers are large enough to hold the object.... You have: - beaker with ...

physics
Mrs. Johnson's kid is trying to drink with a straw that runs through an airtight cork in the top of a bottle of water. Please explain to her kid why he won't get any water.

Math
What did you do to get 275?

Math
Can you show or explain how to do this? Julio uses a scale of 1/8 inch= 1 foot when he paints landscapes. In one painting, a giant sequoia tree is 34.375 inches tall. How tall is the real tree?

Math
The other part was triangle ABC. Side A had the number 8, Side B had 10, and Side C has 16.

Chemistry
Correction: 3Fe2O3(s) + CO(g) ---> 2Fe3O4(s)+ CO2(g) ΔH° = -59kJ Is this right? FeO(s) + CO(g) ---> Fe(s) +CO2(g) ΔH° = -28/2 ΔH° = -14

Chemistry
In the recovery of iron from iron ore, the reduction of the ore is actually accomplished by reactions involving carbon monoxide. Use the following thermochemical equations, Fe2O2(s) + 3CO(g) ---> 2Fe(s) +3CO2(g) ΔH° = -28kJ 3Fe2O2(s) + CO(g) ---> 2Fe3O4(s)+ CO2(...

Chem
What simplifying assumptions do we usually make in working problems involving equilibria of salts of polyprotic acids? Why are they usually valid? Answer by selecting all true statements. Are the answers: a,b,d,and f A)If the two ionization constants are not very different the...

Chemistry
Is this correct? (x ^ 2) / 2.0 = 5.0 x 10 ^ -2 x = 3.162E-1 = [H +] = [H2PO3-] pH = -log (3.162E-1) = 0.50

Chemistry
x^1 - 6.25E-3 + 2.0625E-4 = 0 x = {-(-6.25E-3) +/- sqrt[(6,25E-3)^2 - (4*1*2.0625E-4)]}/(2*1) x = -1.089E-2 (Not x) or 1.714E-2 pOH = -log(1.714E-2 = 1.76 pH = 14-1.76 = 12.24

Chemistry
Is this the right answer? Kb = 1E-14 / 1.6E-12 = 6.26E-3 x^2/-0.033 = 6.26E-3 x = 1.436E-2 pOH= -log(1.436E-2)= 1.84 pH= 14 - 1.84 = 12.16

helper
helper look for my question and help me please

math
is the answer 151 base 9

math
anyone?

math
sorry it was with base 9 in both numbers

math
what do they mean by find the sum of 28g +14g and how do I do it

math
If Will gives Molly $9, he will have the same amount of money as her. If Molly gives Will $9, the ratio of the money she has to the money Will has will be 1 : 2. How much money does Will have in the beginning?

literature
okay thsnks

literature
is he comparing his spirit to winter or to spring? that is what i am having a hard time finding.

literature
It is not incredible how much my eyes see It is snowing on the flowery almond tree It is snowing upon the snow. This winter my spirit is like an early spring, it is like a flowering almond tree (check that word floroido because there is no such word!) under the snow. It is too...

literature
In invierno tardio by antonio colinas what is he comparing his spirit to? No es increíble cuanto ven mis ojos: nieva sobre el almendro florido, nieva sobre la nieve. Este invierno mi ánimo es como una primavera temprana, es como un almendro floroido bajo la nieve...

math
sue had $100 gift card for the candy store. the store had a 15% discount off all retail prices with no sale taxes. there is a $12.00 package fee on each sale. if sue wants to spend exactly $100 including the discount and package fee, what is the greatest total retail price she...

calc
Give the starting value a, the growth rate r, and the continuous growth rate k. Round the answer for r to two decimal places Q = 0.414(e^0.885)^t a = ? r = ?% k = ?% I found a to be 0.414 but when finding the percentage for r and k I got stuck.

everest
What will be the total deduction for social security and Medicare taxes on Juanita's next weekly paycheck of $720 if she has already earned $10,800 this year? Social security tax is 6.2% of wages up to $106,800. Medicare tax is 1.45% of all wages.

Algebra 2
An archer releases an arrow from a shoulder height of 1.39 m. When the arrow hits the target 18 m away, it hits point A. When the target is removed, the arrow lands 45 m away. Find the maximum height of the arrow along its parabolic path. My points are (0,1.39) (18,1.5) (45,0...

chem
The min. energy needed to break a C-Br bond is 288000mol^-1. If one has access to laser with 3 output wavelengths 266,1065,800nm, which wavelength(s) can be used to break that bond? I keep getting 417nm for the wavelength (which is none of the outputs) but the answer is 266nm...

Math
A Norman window has the shape of a rectangle surmounted by a semicircle. (Thus, the diameter of the semicircle is equal to the width of the rectangle.) If the perimeter of the window is 30 ft, find the dimensions of the window so that the greatest possible amount of light is ...

Chemistry
A student was given 100mL of HCL solution in a 250mL beaker and told that the HCL was 0.11M. The student was also given phenolphthalein indicator and 250 ML of 0.1234 M NaOH. The student first filled a buret with NaOH solution. The student then placed an appropriate volume of ...

Math
Explain what benchmark you would use to estimate the number of people that can ride on a bus.

Algerbra 1
What is the order of √5 , -0.1, -5/3 , 0.7, √2 from least to greatest? A. 0.7, √2 , -5/3 , √5 , –0.1 B. √5, √2 , 0.7, -5/3 , –0.1 C. -5/3 , –0.1, 0.7, √2 ,√5 D. –0.1, 0.7, √2 , √5, -5/3

Algerbra 1
What is the simplified form of the expression? -(8d - 3w) A. 8d - 3w B. -8d + 3w C. 8d + 3w D. -8d - 3w

Physical Science
Because light travels in a straight line and casts a shadow, Isaac Newton hypothesized that light is A. a stream of particles. B. a wave. C. heat.

Physical Science
Which kind of light is used to carry information through optical fibers? A. fluorescent B. sodium-vapor light C. laser

maths
identify and describe 3 environmental health hazards that causes ill health

CHEMISTRY URGENT!
PENILE ERECTION DYSFUNCTION

math
Draw and label line BN. Draw and label point T on it

Physics
1. A 2.5kg rock is dropped from a 350m cliff. It hits the ground with a speed of 60 m/s. What percent of its mechanical energy was lost to air resistance? -the answer is 48% 2. A motor uses 5500J to lift a 35kg object a vertical distance of 12m. What is the efficiency of the ...

physics
thanks a lot i appreciate it

physics
A hypodermic needle consists of a plunger of circular cross-section that slides inside a hollow cylindrical syringe. When the plunger is pushed, the contents of the syringe are forced through a hollow needle (also of circular cross section). If a 4.0- N force is applied to the...

physics-HS
Just as a car tops a 49 meter high hill with a speed of 77 km/h it runs out of gas and coasts from there, without friction or drag. How high, to the nearest meter, will the car coast up the next hill? plzzz help!

health informatics
how is emerging technology influencing healthcare? and give an example. all what i know is that they are basiclly new technologies and my example is about tissue engineering but the problem is that i don't know how it influences the healthcare!!! so please please your ...

Trig
The set of solution(s) of 2 cos^2 (θ) - 13 cos(θ) + 6 = 0 that is(are) in the interval (0,π/2) is one of following a. {π/6} b. {π/3} c. {π/4} d. {π/3, π/6} e. {π/6, π/4}

algebra
Kenny buys mixed nuts at a corner market for per pound. The cost is a function of the number of pounds of nuts bought. What is the graph of the function? Is the function continuous or discrete?

biology!!
why do Mountain dwellers have higher averages of hemoglobin than people living in coastal areas?

science-biology
A family member recently found out her child's blood group was AB+ yet hers is O+. i'm suppose to explain this oddity but i don't know how? so please help me!!! thanks

science-biology
A family member recently found out her child's blood group was AB+ yet hers is O+. i'm suppose to explain this oddity but i don't know how? so please help me!!! thanks

Sociology
Which sociological perspective holds the view that people create their social worlds through interaction and manipulation of symbols? A. Functionalist B. Conflict C. Interactionist D. Global

Chemistry
Compare and Contrast the atomic theories proposed by Democritus and John Dalton.

10th grade
change 114/8 to a mixed fraction in simplest form

4th grade
It should be groups of not times

physics
A student bikes to school by traveling first d_N = 1.10 \rm {miles} north, then d_W = 0.500 \rm {miles} west, and finally d_S = 0.200 \rm {miles} south. If a bird were to start out from the origin (where the student starts) and fly directly (in a straight line) to the school, ...

SCIENCE - CLIMATE - ALBEDO
what is the connection between the amount of albedo and energy absorbed?

Physics
A race car traveling at 44 m/s is accelerated to a velocity of 22 m/s over an 11 s interval. What is the displacement of this time? (Could you show how you got the answer?) Thank you

science
Which requires more work - running around the block or walking around the block?

math
I want to creat a line graph.My range is 40-140 for my y-axis, I wanted to know can I plot my graph so I start with 40. Imagine this is my graph can I start with 40 and increase with incraments of 5: 0,40,45, 50... If this is not correct then what is the the proper increments...

english( racism)
I am writing about racism in los angeles, and I have to use newspaper articles. I wanted to show that African earn less money than whites. Also their are more African americans behind prision bars. however, I cannot find anything along these lines. It has to be something from ...

ell
1}why do desert people cover them selves from head to toe? 2}why do some animals stay underground during the day? please write soon thank you

chem
2Na(s) + 2H2O(l) ==> 2Na^+(aq) + 2OH^-(aq) + H2(g) What is the the net ionic equation because it doesn't look like their is any spectator ions.

chem
The molecular formula is: Na(s)+ H2O(l)---->NaOH(aq)+H2(g) This is showing a single displacement reaction.I am not sure how to show the complete ionic equation, this is what I have so far: Na+(s)+ H+ H+O2-(l)---->Na+OH-(aq)+H2+(g) Is this how you show it?

chemistry
In my chemistry lab we decomposed lead (iv) oxide by heating it and then placing a wooden splint(test the evloved gas) into the mouth of the test tube. The color changed into red lead ( Pb304).Then we reheated the sample again and it turned to PbO. I do not understand why the ...

English(work cited page)
Is this correct? Colombo, Gary, Robert Cullen, and Bonnie Lisle. “Learning Power.” Rereading America: Cultural Contexts for Critical Thinking and Writing. Ed. Gary Colombo, Robert Cullen, and Bonnie Lisle. 7th ed. Boston: Bedford/St. Martin’s, 2007: 115-119.

English(work cited page)
I am trying to cite an article in Rereading America, but it was written by the editors of the book. I am having a hardtime citing it. Also its suppose to be in MLA format.

chemistry
no reaction

Math
Simplify. -81^1/4

history
That's what I would go with.

12th grade
A Lesson Before Dying " I had gone to barbershops;I had stood on street corners, and i had gone to many suppers in the quarter.But i had never really listened to what was being said.Then i began to listen, to listen closely to how they taked about their heroes, how they ...

3rd grade
c 2 and 5 trump broke the computer

Math
150 students sat exams. The following elements were calculated ΣFX = 10200 Σ(x-μ)F = 196348 Determine the number of students whose marks were within 2 standard deviations of the mean score

civics/ minnesota state goverment
how many state constitutions has MN had?

Science
Describe briefly a general method that could be used to find the density of a substance. that the question im not quite sure of the answer some help would be nice.... thank you!

History
What factors motivated King Leopold of Belgium to seek ownership of the Congo region? http://en.wikipedia.org/wiki/L%C3%A9opold_II_of_Belgium Thank you for using the Jiskha Homework Help Forum. Hopefully you have a good history of the Congo. I'm sure we've provided ...