# Posts by Fernando

Total # Posts: 49

math
An arithmetic series is such that the 10th term is 40 and the sum of the first 10 terms is 265. Find the sum of the first 20 terms.

maths
the value of a car depreciate by 13% of it value in the first year. in the subsequent year the depreciation is 8% of its value at the beginning of the year.the value of the car when new is \$45000. find its value when it is four years old.

Algebra
rise over run

chemistry
the wavelength(nm)of a ball bearing with a mass of 10g, and a velocity of 10cm/s is what?

Physics
A block is released from rest at the top of an inclined plane. The height of the plane is 5.00 m and it makes an angle of 30.0 degrees with the horizontal . The coefficient of kinetic friction between block and surface is 0.200. What is the speed of the block (in m/s) when it ...

science
how fast must a 2500 kg bus move to have a momentum of 75000 kg m/sec?

Algebra 1 (Reiny or Kuai)
or even better you could say that x+y=0 Algebra teachers like it more :)

Algebra 1 (Reiny or Kuai)
x=-y so that would be the general expresion

Spanish
Yes that's right

pre-algebra
There are 1,400 students in a school.The number of girls is 3/4 the number of boys.How many students are in the other grade levels if 1/6 of the girls and 1/5 of the boys in first grade?

computer science
draw a level 0 diagram as well as a context diagram for the following scenario When renting a car from Banz Car Rental Agency, persons renting a car from the agency will be given a brochure of the type of vehicle, insurance on vehicle and the rental conditions of the vehicle, ...

Biology
Matching a donor's blood and a patient's blood is critical in transfusions. If someone with type A+ blood receives type AB+, he may have a severe hemolytic reaction. This can destroy many of his red cells and quickly kill him. While blood-typing and cross matching are ...

PHYSICAL
A SIMPLE MACHINE PRODUCE 25 JOULES, WHAT IS THE OUTPUT WORK FOR EVERY 50 JOULES OF INPUT WORK. WHAT IS THE EFFICIENCY OF THIS MACHINE?

social studies
Mesopotamia

calc 3
A pilot is flying a Cessna airplane at 180 mph (airspeed).He would like to fly in the direction N45W, but there is a 32 mph wind in the S60W direction.What direction should the pilot set his course for in order to fly along his desired track? What will his speed relative to ...

College Math
In a suburb, housing costs have been increasing at 5.2% per year compounded annually for the past 8 years. A house worth \$260,000 now would have had what value 8 years ago?

Algebra
Solve for x: logx +log(x-5)=2

calculus
find the constants a and b so that the function is continuous on the entire real line. F(x)= 3, x≤-1 ax+b, -1<x<2 -3,x≥2 Help???

calculus
find the constants a and b so that the function is continuous on the entire real line. F(x)= 3, x≤-1 ax+b, -1<x<2 -3,x≥2 Help???

Physics
What is the typical wavelength of an X-ray ? I searched google and I couldn't find it. If you know the answer I'd appreciate it .

A student doing Young's experiment measures a distance of 6.0 cm between the first and seventh nodal points on a screen located 3.0 m from the slit plate. a) if the slit seperation is 220 x10 to the -6, what is the wave length of light being used ? b) what colour is the ...

assignment homehork
A national homebuilder builds single-family homes and condominium-style townhouses. The Excel file House Sales provides information on the selling price, lot cost, type of home, and region of the country (M = Midwest, S = South) for closing during one month. Use Pivot Tables ...

English
Can Passive voice be used with all Conditional sentences? or are there some specific conditionals (.e.g first, zero etc) where passive voice can be used?

statistic
The Excel file MBA Student survey provides data on a sample of students social and study habits. Use pivotTables to find the average age , number of nights out per week, and study hours per week by gender, whether the student is international or not, and undergraduate ...

algebra2
Suppose you invest \$2500 at an annual interest rate of 3% compounded continuously. How much will you have in the account after 7 years? Round the solution to the nearest dollar. ?

math
a large pipe can empty a pool in 6hours and a smaller pipe can empty the same pool in 9 hours. how long will it take both pipes to empty the pool.

Physics
I tried that... I get L/(L+sqrt(M2-M1)) but that's not it...

Physics
A spaceship of mass m is located between two planets of masses M1 and M2; the distance between the two planets is L. Assume that L is much larger that the radius of either planet. What is the position of the spacecraft (given as a function of L, M1, and M2) if the net force on...

Oh I got the answer.... 2.21E-6

The moon causes tides because the gravitational force it exerts differs between the side of the Earth nearest the Moon and that farthest from the Moon. Find the difference in the accelerations toward the Moon of objects on the nearest and farthest sides of the Earth.

Physics
Thanks... now I understand, but when I choose B in the first one it says that it's wrong...

Physics
An ice skater spins with her arms extended and then pulls her arms in and spins faster. Which statement is correct? A. Her kinetic energy of rotation increases because of the work she does to pull her arms in. B. Her kinetic energy of rotation does not change because, by ...

Calculus (pleas help!)
Find constants a and b in the function f(x)=axe^bx such that f(1/8)=1 and the function has a local maximum at x=1/8. a= b= Please help me with this one...

math
the dimensions of a rectangle are such that its length is 3 inches more than its width. if the length were double and if the width were decreased by 1 inch, the area would be increased by 66inches ^2. What are the length and width of the rectangle?

trig
sinx+cosxcot=csc

Math
Write each complex number in rectangular form? I need help with this. :/ 2(cos120°+i sin 120°) and 4(cos 7π/4 + i sin 7π/4) ?

what are some examples for chemical change that easy and safe to take to school for school project

What is the buoyancy force on a 15 g object which displaces 60 ml of water?

math
70% right?

Physics

College Chemistry
A mixture of He and O2 is placed in a 4.00L flask at 32 degrees Celsius. The partial pressure of the He is 2.7 atm and the partial pressure of the O2 is 1.4 atm. What is the mole fraction of O2?? I don't understand how to do this.

Geography
The soil of much of the steppe region of Northern Eurasia is very fertile and productive. lacking in minerals and unproductive. too cold to produce much food. heavily fertilized with chemicals to make it marginally productive.

Science
Whats the source for the easterlies?