# Posts by Valentina

Total # Posts: 52

**Math**

actually the right expresion is 100-(5x4)

**PHYICS URGENT URGENT PLEASE PLEASE PLEASE HELP ME!**

A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (b) Work out and add the numerical values of ...

**PHYSICS URGENT URGENT URGENT URGENT HELP NEEDED!!!**

That doesn't help me because I still don't understand it. Please can you at least direct me on how to go about the question as my work is due very soon.

**PHYSICS URGENT URGENT URGENT URGENT HELP NEEDED!!!**

weight ladder plus floor upward: 750 + 20.0= 770N wall force + friction at base: 20.0 + 0.40= 20.40N I have no idea what you mean about sum moments about any point.

**PHYSICS URGENT URGENT URGENT URGENT HELP NEEDED!!!**

A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (b) Work out and add the numerical values of ...

**Physics**

I have completed a but I just don't understand b and c. Please help me asap!!!!

**PHYSICS**

A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (b) Work out and add the numerical values of ...

**Physics**

A uniform ladder of length 20.0m and weight 750 N is propped up against a smooth vertical wall with its lower end on a rough horizontal surface. The coefficient of friction between the ladder and this horizontal surface is 0.40. (a) Draw a diagram for the ladder showing all ...

**Physics**

A ball of mass 0.15kg is dropped from a height of 1.0m onto a flat surface and rebounds to a height of 0.35m. Calculate: (a) The speed of the ball just before the impact, (b) The speed of the ball just after impact, (c) The change of momentum, (d) The force of impact, if the ...

**Math**

A car and a truck leave the park at the same time, heading in opposite directions. when they are 350 miles apart, the car has gone 70 miles further than the truck. How far has the car traveled? Can someone please help me I am horrible in word problems

**Math please help**

Colombian coffee beans cost $5.50/lb while Peruvian coffee beans cost $4.25/lb. We want to mix the beans together so as to produce a 40 lb bag costing $4.60/ lb. How many pounds of each type of beans shouold be used ? Please help and show work

**Chem**

Write a balanced equation for: 1. beta decay of iodine-138 2. capture of an electron by cadmium-104

**Chem**

Write the two balanced equations, one for the incomplete combustion of methane (to form carbon monoxide and water vapor), and another one for the complete combustion of methane (forming carbon dioxide and whatever vapor). What are the conditions, at which do you think the ...

**math**

A scale drawing of an American flag is 14 inches long and 6 inches tall. The actual flag is 3 feet tall. a. True or False, the scale of the drawing is 2 in. : 1 ft. is it false? b. What is the perimeter of the american flag in the scale drawing? c. What is the area of the ...

**math**

Ashley uses 1/4 package of raisins for fruit cake. She then uses 1/9 of the remainder for the muffins.What fraction of the package of raisins does she have left? My answer is 2/3. 4/4-1/4=3/4(remainder). then 3/4 x 1/9= 1/12 (muffins)then 3/4-1/12=2/3(left) Is it ...

**math**

this is the 5th grade problem. This is exactly what I have. Rosa and her friends used 1 2/3 quart of paint on Monday and 1 3/4 quart of pain on Tuesday.How much paint will Rosa and her friends need on Wednesday.If Rosa If Rosa and her friends have 3/4 quart of pain left, do ...

**math**

That is all information I have.My answer is: they need on Wed 1 4/5(Monday 1 2/3, Tuesday 1 3/4) So 3/4 is not enough.Is it correct?

**math**

Rosa and her friends used 1 2/3 quart of paint on Monday and 1 3/4 quart of pain on Tuesday. If Rosa and her friends have 3/4 quart of pain left, do they have enough pain to finish the job on Wednesday?

**math**

-4x-31

**english**

u are correct except for number 2

**english**

1. family, friends, and school work. 2. make us feel wise for buying our home years ago. 3. garden and return feeling much more relaxed.

**math**

Help NOW PLEASEEEE

**math**

Yvonne put $4,000 in a savings account. At the end of 3 years, the account had earned $960 in simple interest. A. how much does she have in her account at the end of 3 years? B. at what annual simple interest rate did the account grow? c. how many more dollars would she have ...

**Science**

Data

**math**

cindy can type 50 words a minute. At this rate, how many words can she type in a half hour?

**Algebra**

Solve the exponential by expressing each side as a power of the same base and then equating exponents. 5^x-2/4=squaroots 5 please help. Thanks!

**social studies**

what significant contribution to Russian history did Prince Ivan III make?

**science**

which of the following statements accurately describes the development of the geologic time scale?

**Math**

Mr. Singh deposited $170 in his bank. The number of $5 bills was three times the number of $10 bills and the number of one dollar bills was 30 more than the number of five dollar bills how many bills of each type did he deposit

**education**

In a minimum of 300 words, discuss at least five selection criteria you would use to “weed” the sites, explaining why you chose the criteria you

**chemistry**

A 0.194 g sample of compound is vaporized to fill a 100.0 mL vessel at 750. torr and 100.C. What is the molar mass and molecular formula?

**math**

432-49

**please help me**

1/2minutes

**physics**

12

**math help pls**

3 is a

**Math**

44% off of $158

**English**

Thanks so much it was on our homework.... Our teacher said that she would give us a break so she gave us a sheet of word puzzles.

**English**

Figure out this word l_d_bu_ Please Help Me!!!!!!!!!!

**Math**

What is the volume of a cone with a radius of 3 cm and a height of 6 cm? I can't get this one right for some reason!

**Chemistry.**

Which of the following changes will increase the amount of solid solute able to be dissolved in a liter of liquid water? decreasing pressure increasing temperature decreasing temperature increasing surface area

**chemistry**

How many grams of Lead (II) Nitrate are required to make a 350mL solution of 2.5M Pb2+?-

**chemistry**

if you react one mole of sodium hyrdoxide with excess copper(II) sulfate, how many moles of copper(II) hydroxid are produced?

**chemistry**

if 2.7 moles od sodium carbonate reacts with 5 moles of copper(II) sulfate, how many grams of sodium sulfate will be produced?

**chemistry**

if 25 grams of copper reacti with 70 grams of sodium carbonate, identify the limiting reagent.

**chemistry**

If 2 moled of copper(II) sulfate react with 3 moles of sodium carbonate, identify the limiting reagent.

**chemistry**

write a balanced equation for the reaction of copper(II) sulfate with sodium carbonate to produce copper(II) carbonate and sodium sulfate

**chemistry**

Explain what a limiting agent is and how to identify it

**chemistry**

what are the theoretical mole ratios of copper(II) hydroxide and sodium sulfate?

**chemistry**

Explain how to make a 1.5M solution of copper (II) sulfate with a volume of 250 mL.

**chemistry**

Why will a new nail react faster in copper sulfate solution than an old, rusty nail?

**chemistry**

If you submerge a silver teaspoon in copper sulfate solution, what reaction would you expect and why?

**Country Reports**

dont know but i got iceland for my report 2!