# Posts by Bob

Total # Posts: 3,283

**calculus**

actually an ODE question(but there's no diff. eq. subforum) (y^2)(dy/dx)+y^3/x =2/x^2 using substitution u(x)=y^3 so I've been doing a few of these and getting them all wrong and this problem... I don't know where to start. I tried (1/u)(du/dx)+u/x(du/dx)=2/x^2 but...

**materials science**

Consider a copper lattice with an excessive average of one vacancy in every 100 unit cells. What will be its density? Compare this to the theoretical density of copper.

**Chemistry**

How many grams of CO2 are formed when 32 g of O2 reacts with 23 g of C2H5OH?

**algebra**

parking lot had a length that is 7 yards greater than thre width. the area of the lot is 450 square yards. what is the length and width?

**Chemistry**

Using VSEPR what is the shape of ammonia (NH3) and water (H2O) when bonded to a hydrogen bond?

**Chemistry**

Using VSEPR what is the shape of ammonia (NH3) and water (H2O)?

**Math**

Rebecca gives gifts to 12 employees. Each gift is in a box that is 12 inches by 10 inches by 3 inches. How much wrapping paper does Rebecca need to completely the cover the boxes? F. 360 in(insert exponent 2) G. 1,720 in(insert exponent 2) H. 4,320 in(insert exponent 2) J. 14,...

**Chemistry**

1000

**Math**

21

**math**

help me pls

**Chemistry Lab**

we reacted acetic acid with butanol and formed butyl acetate which is supposed to smell like banana but it smelled like sharpie/nail polish remover why might this be

**chemistry**

An insulated beaker contains 250.0 grams of water at 25C. Exactly 41.6 g of a metal at 100.0C was dropped in the beaker. The final temperature of the water was 26.4C. Assuming that no heat is lost in any other way, calculate the specific heat of the metal.

**Physics**

A wooden block of mass 29.0 kg sits on a horizontal table. A wire of negligible mass is attached to the right side of the block and goes over a pulley (also of negligible mass, and frictionless), where it is allowed to dangle vertically. When a mass of 15.5 kg is attached to ...

**Physics**

As above, as the x-value for particle 3 approaches infinity the only force acting on particle 2 is from particle 1. The asymptote is the value of that force. Set the equation for (kq1q2)/(r^2) = 1.370e-25N and solve for q2. Note that you can solve for r with the knowledge that...

**physics**

An astronaut in his space suit has a total mass of 275 kg. His weight on the asteroid Erewhon is 0.3 N. What is the acceleration of gravity on Erewhon?

**math**

what is the sum of the odd numbers 1-2009

**pre cal**

Given triangle ABC, A = 120, a = 8, b = 3; determine B to the nearest whole degree

**physics**

Hey there, Did anyone give you an answer? I'm just wondering because I too have a similar question.

**physics**

Friction provides the force needed for a car to travel around a flat, circular race track. What is the maximum speed at which a car can safely travel if the radius of the track is 82.0 m and the coefficient of friction is 0.39?

**Chemistry**

1620 J

**finance**

12.2%

**chemisty**

The molar heat capacity of C6H6(ℓ) is 136 J/mol ·◦C and of C6H6(g) is 81.6 J/mol · ◦C. The molar heat of fusion for benzene is 9.92 kJ/mol and its molar heat of vaporization is 30.8 kJ/mol. The melting point of benzene is 5.5 ◦C, its ...

**chemistry**

When 0.373 g of compound X is burned completely in a bomb calorimeter containing 3000 g of water, a temperature rise of 0.341 C is observed. What is ∆Urxn for the combustion of compound X? The hardware component of the calorimeter has a heat capacity of 3.19 kJ/ ◦C...

**math**

4square root.Of 5

**PARALLELOGRAM WRITING A PROOF**

given 1.vx is con to xt by csctc ux con xs 2. x is midpoint of those 2 lines 3.vuts is a paarlelogram

**physics**

A 640-kg racing car completes one lap in 14.3 s around a circular track with a radius of 45.0 m. The car moves at constant speed. (a) What is the acceleration of the car? m/s2 (b) What force must the track exert on the tires to produce this acceleration?

**Physics**

65

**Physics**

A 18 kg object and a 26 kg object are connected by a massless compressed spring and rest on a frictionless table. After the spring is released, the object with the smaller mass has a velocity of 2 m/s to the left. What is the velocity of the object with the larger mass?

**Math**

Five employees at the Wild Fowl Publishing Company each come to work by a different one of five means: car, railroad, subway, and walking. They hold these positions at the company: art director, editor, publisher, receptionist, and secretary. Two of them are men named Finch ...

**math**

A popular new secretary at the law firm of Farnsworth, Newman, O’Malley, Price, and Reynolds, is taken to lunch by a different one of those five men on each of her first week on the job. Each man took her to eat at a different one of these five types of food: Chinese, ...

**chem**

How many grams are in 3.6 moles of agcl2?

**math**

what is equivalent to 98% o.49 or 100/98 or o.98 or 49/100

**6 th grade Math**

You can find the total number of different 4-digit numbers of choices for each digit (9) to the number of digits (4), or 9 to the 4th power. Based on this pattern, how many different 5-digit numbers could you make from the digits 1 through 8?

**math 6th grade**

How to write out 10 the negative 6?

**math 6th grade**

How to write out 10 to the negetive two?

**math 6th grade**

(1/2) to the 5th power= Need to know how to write this?

**chemistry**

Atom X has atomic mass (A) = 40 and atomic number (Z) = 20. Atom Y has A = 42 and Z = 20. How are these two atoms related?

**Math Grade 3**

You move the decimal to the left for example: 123 divide by 10 is 12.3

**chemistry**

. Compound C (MW = 550) is provided at a concentration of 25g/100mL. 1mL is taken and compound D is to be added (MW = 1025, concentration = 75mM) to give a final ratio of compound C:D of 4:1 moles ratio. What volume of compound D is to be added? ***Dr BOB222 THE 4:1 RATIO IS ...

**chemistry**

6. Compound C (MW = 550) is provided at a concentration of 25g/100mL. 1mL is taken and compound D is to be added (MW = 1025, concentration = 75mM) to give a final ratio of compound C:D of 4:1 moles ratio. What volume of compound D is to be added?

**chemistry**

6. Compound C (MW = 550) is provided at a concentration of 25g/100mL. 1mL is taken and compound D is to be added (MW = 1025, concentration = 75mM) to give a final ratio of compound C:D of 4:1 moles ratio. What volume of compound D is to be added?

**chemistry**

by moles

**chemistry**

6. Compound C (MW = 550) is provided at a concentration of 25g/100mL. 1mL is taken and compound D is to be added (MW = 1025, concentration = 75mM) to give a final ratio of compound C:D of 4:1 moles ratio. What volume of compound D is to be added?

**can you please look over my answers? clauses**

Select the abbreviation that tells how the italicized noun clause is used. S-subject, DO-direct object, SC-subject complement, OP-object of preposition A lecture on cleanliness was not what the children wanted to hear.

**trig**

The manufacturer of a propeller for a small aircraft mandates a maximum operating angular velocity of 300 rad/s. Determine whether it is safe to install this propeller whose aircraft whose engine is expected to run at a maximum of 2800 rpm

**math**

163.8

**chemistry**

the ratio is moles

**chemistry**

Compound C (MW = 550) is provided at a concentration of 25g/100mL. 1mL is taken and compound D is to be added (MW = 1025, concentration = 75mM) to give a final ratio of compound C:D of 4:1. What volume of compound D is to be added?

**science**

10.8kg

**help!!!!**

A navy destroyer is exactly 68 miles North of an aircraft carrier, which is travelling West 21 degrees North at 18 mph. what speed and bearing must the destroyer maintain if it is to reach the aircraft carrier in exactly 3 hrs? is it 226mph?

**pre calc**

each of three circles touches the other 2.circle A has a radius of 8 cm. circle B has a radius of 4 cm.circle C has a radius of 1 cm.a triangle is formed by connecting the centers of the 3 triangles. determine the largest angle for the triangle and in which circle is the ...

**pre calc**

you are 7 miles north and 4 miles west of a cabin.how far are you from the cabin? on what bearing must you walk to reach the cabin?

**math**

find all solutions on 0 is greater than or equal to theta < 2pi cos theta= 2sqrt3/3 4-1/2sin theta= (-16+sqrt3)/4 3(sqrt3)= -3cot theta -2=-1-2sin theta

**math**

the hour hand of a clock is 5 inches long and the minute hand is 6 inches long. determine the distance between the tips of the hands at 11:40 pm????

**science**

Is melting ice a physical or chemical change? I think it is a physical change. Am I correct?

**geometry**

do ur own homework

**la poetry**

i need help with narrative soccer

**physics**

An 77 person stands on a uniform ladder 4.0 long, that weighs 100 , as shown in the figure . The floor is rough; hence, it exerts both a normal force, , and a frictional force, , on the ladder. The wall, on the other hand, is frictionless; it exerts only a normal force, . the ...

**Physics**

A 86.0 kg diver falls from rest into a swimming pool from a height of 6.3 m. It takes 1.44 s for the diver to stop after entering the water. Find the magnitude of the average net force exerted on the diver during that time.

**8th Grade**

I love you and you should never forget that. Okay senpai remember me for centuries. I will love you to the end of time.

**physics**

Gas is conﬁned in a tank at a pressure of 10 atm and a temperature of 14◦C. If 58 percent of the gas is withdrawn and the temperature is raised to 50◦C, what is the new pressure in the tank?

**chemistry**

4.89 atmospheres

**Math**

Rewrite cos(arcsin(v)) as an algebraic expression in v. i know that the answer is squroot of 1-v^2 but i don't know the process of how to come to this answer. Thanks for the help!

**physics**

A spaceship of mass m travels from the Earth to the Moon along a line that passes through the center of the Earth and the center of the Moon. (a) At what distance from the center of the Earth is the force due to the Earth three times the magnitude of the force due to the Moon?

**math**

WAZUPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP NMY FRIEND HAHA

**math**

HIHIHIH

**calculus**

What is the area under each of the given curves? y=e^x/2 ; x=0 x=1

**Math**

I need this answer too

**Calculus**

for the function F(t)=ln(t^2), let f(t)=F'(t). Write the integral from a to b of f(t) dt and evaluate it with the fundamental theorem of calculus. the integral from 1 to 3 ___ dt= __

**V/CV OR VC/V PATTERN**

GAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHHH RIPPING MY HAIR OUT THIS IS SO HARD

**Economics**

Suppose that some firms in a competitive industry are earning zero economic profits, while others are experiencing losses. All else equal, in the long run, we would expect the number of firms in the industry to A. increase. B. decrease. C. remain the same. D. We do not have ...

**Economics**

If the market price falls below $4.50, the firm will earn A. positive economic profits in the short run. B. negative economic profits in the short run but remain in business. C. negative economic profits in the short run and shut down. D. zero economic profits in the short run.

**Economics**

A long-run supply curve is flatter than a short-run supply curve because A. firms can enter and exit a market more easily in the long run than in the short run. B. long-run supply curves are sometimes downward sloping. C. competitive firms have more control over demand in the ...

**math**

what is 2 times 5

**Physics**

Four particles in the xy plane have the following masses and coordinates: 1 kg at (3 m, 3 m), 2 kg at (-2 m, 4 m), 3 kg at (3 m, -2 m) and 4 kg at (-3 m, -4 m). Find the total moment of inertia about: x-axis? y-axis? z-axis?

**Physics**

thanks

**history**

where can i get facts about winchester cathedral

**Chemistry**

Rank the following atoms in terms of decreasing atomic radius. 1. Na, N, O, Mg, F 2. F, O, N, Mg, Na 3. F, Mg, Na, O, N 4. Na, Mg, N, O, F 5. F, O, N, Na, Mg

**ELA**

Those were great :D But do you have anymore ideas? We need to write at least a full page

**ELA**

Not that kind of funny but like its from this book and here was an example Don't bite your fingernails because the nails will look nasty. But the real reason not to bite your nails is cause when you take off a nail and it goes on the floor it will grow on the floor and it ...

**ELA**

I have to do this project and I have to say what funny stuff could happen if I cleaned my room. I don't know anything funny that could happen. so help me? :D

**math**

i don't know

**physics**

nkkn

**Physics**

(3kg)(8m/s)+ (5kg)(0m/s) 24kg*m/s = (3kg+5kg)vf (8kg)vf 24kg*m/s=(8kg)vf vf=3m/s

**Physics**

150kg*m/s

**Math**

what up

**Math, Please Help!!!**

an engineer designs a satellite dish with a parabolic cross section. The dish is 15 ft wide at the opening and the focus is placed 4 ft from the vertex. find an equation of the parabola. I know how to work this problem, but how do I know that I use the equation y^2 = 4px ...

**READING**

Which line in the poem contains an example of onomatopoeia? A. Line 6 B. Line 7 C. Line 14 D. Line 15 Line 6: and you'll forget all about that broccoli you chop Line 7: Rock candy looks like beautiful glass Line 14: but spinach tastes all gritty and sandy Line 15: Taffy is...

**Reading**

Is it LINE 15?

**Reading**

Which line in the poem contains an example of onomatopoeia? A. Line 6 B. Line 7 C. Line 14 D. Line 15 Line 6: and you'll forget all about that broccoli you chop Line 7: Rock candy looks like beautiful glass Line 14: but spinach tastes all gritty and sandy Line 15: Taffy is...

**Chemistry**

When non-polar materials suddenly become polarized the most likely reason is due to:

**Reading**

WAIT no line 15

**Reading**

Which line in the poem contains an example of onomatopoeia? A. Line 6 B. Line 7 C. Line 14 D. Line 15 Line 6: and you'll forget all about that broccoli you chop Line 7: Rock candy looks like beautiful glass Line 14: but spinach tastes all gritty and sandy Line 15: Taffy is...

**Reading**

Since the 1st line ends with me and the next line ends with disagree The first line is A and the next line is B?? Then the third line ends with true and the next line ends with chew so its AABB?

**Reading**

Does me and disagree rhyme? it doesn't right?

**Reading**

Ok heres some of it Mom says that vegetables are good for me, but I am afraid I must disagree. Candy is better. I just know it's true! Because bubble gum helps me learn how to chew

**Reading**

What is the rhyme scheme of "Great Glorious Gobs"? A. ABAB B. BBBA C. AABB D. AABA

**Social Studies**

what is your primary duty if you are at electoral college