Posts by Lena
Total # Posts: 1,054

Physics
Your vertical spring accelerometer has a 200 g mass hanging from it. You climb aboard the roller coaster and watch the accelerometer read 0.4 g for 3 seconds while descending the first peak and then change to 1.5 g for 2 seconds while climbing the second peak. Your fully ... 
world history
how did the cold war influence events in the postwar period I can't find this in my textbook. could someone explain please 
Math (Helping my brother)
$2.15 per page p= number of pages p=28 2.15p= 2.15(28)+cost of supplies supplies= 5 2.15(28)+5=... 
biology
would you consider that eukaryotic cells got rid of their cell wall to benefit as a heterotroph? They must of had a cell wall to begin with because all cells come from prokaryotic cells. 
biology
I appreciate your response. According to what is said on the link provided, would you consider that eukaryotic cells got rid of their cell wall to benefit as a heterotroph? 
biology
did cells loose their cell wall due to evolution or did they never have a cell wall to begin with? pls explain 
Math
yup, then solve for x. 
Biology
cellular respiration 
math
Using the quadratic formula; I have to solve 8(asquared)a+2=0 a=8, b=1, c=2 
Math
5 and 2 
Math
Compare partial products and regrouping. Describe how the methods are alike and different. ♡♡♡♡????????? 
Math
Kurt cut pizzas into wedges measuring 40 degrees. If each person eats one piece of pizza, how many people could he feed with two whole pizzas? 
Math (Rounding #s)
How would I round 0.598958333 to the thousandths? Would it be 0.6000 or 0.5990? Also, could you please tell me why the answer is what it is? If I had something like, 0.55998, as in two 9s in the row, what would I do then? Thank you! 
Social studies
so what is it?! 
home economics
what are the characteristics of dirt? 
math
I forgot to check it. But the answer is 26.Also I am in third grade!!!! 
math
2x9=18 and 2x4=36.18+36=54. 
math
I still don't get it. 
math
What is the perimeter of 4 feet wide and 9 feet long????? 
math
Scientists are conducting an experiment with a gas in a sealed container. The mass of the gas is measured, and the scientists realize that the gas is leaking over time in a linear way. Six minutes since the experiment started, the gas had a mass of 144 grams. Fourteen minutes ... 
Math
I think it's C. 
Language Arts Checking answer
I think it's C. 
science
How do animals find their shelter? 
Math
Using the distance function s(t) = t2 + 4t + 30, "s" is in feet and "t" is in seconds, find the velocity function, v(t), and acceleration function, a(t). 
Math
6!Thank you!!!! 
Math
If you mind I have another problem....I am a product.One of my factors is 3.The other factor is 2 times as great.What number am I??? 
Math
I am a product.One of my factors is 7.The sum of my factors equals 11.What number am I? 
Math
I am a number that is four times the product of 2 and 3.One of my factors is 4.What is my other factor? 
Math Homework
Directions: Find the fourthorder derivative. 1.) f''(x)=7x^5/2, f(^iv)(x) 2.) f''(x)=8x^7/5, f(^iv)(x) 
Chemistry
Why does the temperature in exothermic reactions increase, reach a maximum, and then decrease? 
Math Decimals
The answer is 86.23 
Math (ASAP)
I really need help with this. Thank you! Directions: Using the limit process, find the limit of the following function below. f(x) = 2 – x^2 
Math Help
Directions: Using the limit process, find the limit of the following function below. f(x) = 2 – x^2 
Math Help
Directions: Using the limit process, find the limit of the following function below. f(x) = 2 – x^2 
Madison
Elliot put 7 cups of tea into the pitcher shown. How many more cups of tea does he need to fill the pitcher? (1 quart = 4 cups) 
physical
1.What kind of information is indicated by the graph of the acceleration due to gravity versus ball¡¯s mass if the slope of the curve is zero? 
Math
Beginning at age 35, Ms. Trinh invests $4000 each year into an IRA account until she retires. When she retires she plans to withdraw equal amounts each year that will deplete the account when she is 80. Find the annual amounts she will receive for each of the following ... 
Physic
The concepts in this problem are similar to those in MultipleConcept Example 4, except that the force doing the work in this problem is the tension in the cable. A rescue helicopter lifts a 75.4kg person straight up by means of a cable. The person has an upward acceleration ... 
Physic
A 16kg sled is being pulled along the horizontal snowcovered ground by a horizontal force of 27 N. Starting from rest, the sled attains a speed of 2.2 m/s in 9.6 m. Find the coefficient of kinetic friction between the runners of the sled and the snow. 
Physic
A 287kg crate is being pushed across a horizontal floor by a force P that makes an angle of 25.6 ° below the horizontal. The coefficient of kinetic friction is 0.236. What should be the magnitude of P, so that the net work done by it and the kinetic frictional force is zero? 
Physic
A person pulls a toboggan for a distance of 43.1 m along the snow with a rope directed 33.3 ° above the snow. The tension in the rope is 109 N. (a) How much work is done on the toboggan by the tension force? (b) How much work is done if the same tension is directed ... 
Physic
A person pushes a 13.7kg shopping cart at a constant velocity for a distance of 16.3 m on a flat horizontal surface. She pushes in a direction 22.2 ° below the horizontal. A 48.7N frictional force opposes the motion of the cart. (a) What is the magnitude of the force ... 
Physic
You are moving into an apartment and take the elevator to the 6th floor. Suppose your weight is 640 N and that of your belongings is 940 N. (a) Determine the work done by the elevator in lifting you and your belongings up to the 6th floor (15.2 m) at a constant velocity. (b) ... 
Chemistry
In an experiment, you dissolve 0.30 g of KHP (MM = 204.22 g/mol) in 20 mL of DI water and titrate the sample with 0.10 M NaOH. Calculate the volume (to the nearest mL) of NaOH required to reach the equivalence point. IS it a) 3 b)15 c)20 d)30 e)100 I have done MV=MV (0.3/204.... 
Physics
31.5 
social studies
it is definitely 2 got 100% on test answer 
MATH
15 FULL CUPS AND 22 HALF CUPS 
MATH
SASHA AND FRANCISCO WERE SELLING LEMONADE FOR $.25 PER HALF CUP AND $.50 PER FULL CUP. AT THE END OF THE DAY THEY HAD COLLECTED $15 AND HAD USED 37 CUPS. HOW MANY FULL CUPS AND HOW MANY HALF CUPS DID THEY SELL? 
ECE 201
Why is it important for teachers to understand students’ culture and backgrounds in an effort to address challenging behavior? 
statistics
Histograph or Bar Graph 
Math
(110) 
physics
if the diamter of a human hair is (50*10^6 m) estimate the volume of hair on your head 
english
what genre is Black Ships Before Troy ~ by Rosemary Sutcliff? 
Physics
A 4.5kg box slides down a 4.1m high frictionless hill, starting from rest, across a 1.7m wide horizontal surface, then hits a horizontal spring with spring constant 490N/m . The other end of the spring is anchored against a wall. The ground under the spring is frictionless... 
Physics
A horizontal spring with spring constant 110N/m is compressed 16cm and used to launch a 2.8kg box across a frictionless, horizontal surface. After the box travels some distance, the surface becomes rough. The coefficient of kinetic friction of the box on the surface is 0.15. ... 
Workplace Skills
I don't know if AJ's termination would show up on a background check, and I was not able to find anything online. 
Workplace Skills
We're supposed to read over the following scenario and provide advice for AJ: AJ has a job that he really likes and pays well, but he is worried he is about to be terminated. He doesn't want to quit his job and give up his excellent pay, but he knows that being fired ... 
Physics
(637) A cyclist is riding on a horizontal frozen meadow. He is turning so that he is tilted at an angle of 60°. Radius of curvature of the bend is 100m. What is the maximum speed of the cyclist? Thank you for your time! 
Physics
(595)Vinyl record spinning at 45rpm. What is the frequency of rotation (in Hz)? What is the orbital time of the vinyl record (in seconds)? 
social studies
What do people in Catalonia celebrate every April 23rd? 
social studies
What major land form and body of water cover much of northern south america? 
Physics
The inner and outer surfaces of a cell membrane carry a negative and positive charge, respectively. Because of these charges, a potential difference of about 0.070 V exists across the membrane. The thickness of the membrane is 0.000000008 m. What is the magnitude of the ... 
world history
How has the global economy changed after the Cold War? 
world history
Ghana but but the movement there was relatively peaceful. Or Algeria 
world history
Which African independence movement is most similar to the movement in Kenya? I'm thinking the one in Haiti but I'm not sure 
Chemistry
what is the pH and pOH of a solution made by adding water to 15 grams of HCl until the volume of the solution is 2500mL? 
math 8th
Now y y'all gonna sit there and do that @jo dirt is correct like y'all weird to say he was wrong cause I just took the test and he is completely right 
Chemistry
ohh okay now i understand. thank you 
Chemistry
so v would be 83mL? 
Chemistry
what volume of concentrated 18M H2SO4 is required to prepare 250mL of a 6.0M solution? how would you solve this problem? i know it has something to do with the molarity formula but no idea how to apply it 
Chemistry Help
1.) Calculate the number of atoms in 2.58 mol antimony. 2.) Determine the mass of 1.45 mol FePO4. 3.) Calculate the number of mol in 6.75 g of NaCl. 4.) What is the volume, in liters, of 2.54 mol methane (CH4) gas?. 5.) What is the percent composition of B4H10? 
proportional relationship
Nxnsbsb 
health
I don't know if you can access this (not sure if this information is free) but there is a review on the negative and positive health effects on alcohol consumption. Since I cannot post the link, here is the reference: Grønbæk, M. (2009). The positive and ... 
physics
a 1.2 kg cart slides eastward down a frictionless ramp from a height of 1.8 m and then onto a horizontal surface where it has a headon elastic collision with a stationary 2.0 kg cart cushioned by an ideal Hooke's law spring. the maximum compression of the spring during ... 
Physics
In a demonstration in physics class, a 1.2 kg dynamics cart starts from rest at the top of a ramp. the ramp is 2.4 m above the ground. the cart then rolls down to the bottom of the ramp, where it collides with a stationary 1.4 kg dynamics cart. Assume that an elastic headon ... 
Physics
please help Ms. SUE!!!! 
ap world history
so Asia? 
ap world history
which region of the world benefited more from the columbian exchange? 
ap world history
how did wheat impact the Americas? 
7th Grade
Cells and Herdity 
ap world history
where did wine originate? 
world history
How did it spread in the periods from 870 B.C.E to about the 18th century, mostly in Greece and Rome 
world history
to what places did wine spread? 
world history
1. How does the story of CocaCola relate to the rise of capitalism and entrepreneurship in the 19th and early 20th c? 2. what is the "iron curtain"? 
math
John's age = Sally's age  3 years Elissa's age = 13 years Sally's age = Elissa's age  3 years = 13 3 = 10 years Now that we know Sally's current age, we can figure out John's age. John's age = 103 = 7 years So if John is 7 years as of now, ... 
math
7.49+2.05/0.500.59 FOLLOW BEDMAS 1) First do the division in the question 7.49+4.10.59 2) Now add and subtract = 11 
Math
So this question is wanting you to identify some sort of pattern. Let's write it out as the following (makes it easier to visualize): 2,8,32,?,?,? Now, I can see a pattern right away. 2 x 4 = 8 8 x 4 = 32 32 x 4 = 128 (month 4) 128 x 4 = ? (month 5) and so on and so forth... 
math
Let's say X represents a full can of paint If X represents a full can on paint, then:  1/8 of X was used in the morning  5/8 of (7/8 of X) was used in the afternoon So you would add the two values together to get a sum 1/8X + 5/8(7/8X) = 1/8X +35/64X =43/64X Therefore 43... 
math
xy=0 x+y = 4 x+y+xy=4+0 2x=4 x=2 Therefore y=2 x=2 y=2 
math
So the formula for the area of this photograph would be the following: area = length x width (let's fill in what we know from the question into this formula) 28 =(2w1) * w (Now let's use the distribution rule and multiply everything in the brackets by 'w') 28... 
Math
Let us call the jar of peanut butter "P" Let us call the loaf of bread "L" Now let us make some mathematical sentences from the information provided to us from the question above. 1P + 3L = $6.70 3P + 1L = $9.32 As you can see, we have 2 unknowns. We want ... 
Maths
1.5 x 10^8 150 000 000 You start with the 0 on the far right (as that is where the decimal place is) and you see how many times you must shift it over (in this case 8) before the number is greater than or equal to 1 but less than 10. 
CHEM HELP!!!
The solubility of AgCl(s) in water at 25 C is 1.33x10^5 M and its deltaH of solution is 65.7 kJ/mol . What is its solubility at 60.1 C ? Please explain how to solve for this!! 
Math
Dr. Jane, couldn't the number 36 also be a possibility as it is greater than 30 but less than 50 and has a 6? 
Math
I don't know how you actually found a value :/ 
Math
Perimeter = S1 + S2 + S3 5x^42x^3+x3= (2x^4 + 2x1) + (2x^4+2x1) + base 5x^42x^3+x3 = 2(2x^4 + 2x1)+ base 5x^42x^3+x3  2(2x^4 + 2x1) = BASE 5x^42x^3+x3 4x^44x+2= BASE 5x^44x^42x^33x1 = BASE 
math
50 people require 4 cups of sugar 1 person will require 4/50 cups of sugar 100 people will require 4/50 x 300 cups of sugar = 24 cups of sugar 6 cups of sugar = 1 bag 1 cup of sugar = 1/6 bag 24 cups of sugar = 1/6 x 24 bag = 4 bags Therefore, 300 people require 4 bags of sugar 
math
In order to paint 144 sq feet it will take 45 minutes In order to paint 1 sq foot it will take 45/144 minutes In order to paint 240 sq feet it will take: 45/144 x 240 minutes = 75 minutes 
math
x^24x+32=0 a =1 b= 4 c= 32 4 +or sq root (4)^2 4(1)(32) 4 +or sq root 16128 4 +or sq root 112 you can't take the sq root of a () number so you can't solve this :/ How did you get 2 +or 2 sqrt7. Perhaps I went wrong somewhere. 
Algebra
What exactly is a trend line? I'm thinking it would be B because they're not asking for the exact line. In fact, if it's a scatter plot there wouldn't be a perfect straight line. I think you're right. It's probably B.