# Posts by Chris

Total # Posts: 2,692

**Math**

1/180

*May 15, 2016*

**math**

a plat form and a building are on the same horizontal plane , the angle of depression of the bottom of the building from the top A of the platform is 39 degree. the angle of elevation of the top D of the building from the top of the platform is 56 degree. given that the ...

*May 12, 2016*

**Chemistry**

When chromium has 26 electrons, how many neutrons and protons does it have and what is it's standard notation

*May 10, 2016*

**Calculus**

Farmer Jones, and his wife, Dr. Jones, decide to build a fence in their field, to keep the sheep safe. Since Dr. Jones is a mathematician, she suggests building fences described by y=4x^2 and x^2+10. Farmer Jones thinks this would be much harder than just building an enclosure...

*May 6, 2016*

**Math 3**

How many times bigger is 8*10^6 than 2*10^2?

*May 6, 2016*

**Maths**

If a car weighing 1,054kg collides with another car and then takes 60 metres to come to rest can the speed at the pint of impact be calculated?

*May 6, 2016*

**Math**

it's 4 because 3+3=6 and 4+2=6

*May 4, 2016*

**Trig**

Problem: A cable from the top of a 60 foot high tower is to be attached to the ground (x) feet from the base of the tower. A) if the cable makes an angle of t radians with the ground when attached, express t as a function of x. B) if t = pi/5, how far is the end of the cable ...

*May 1, 2016*

**PHYSICS SPECIFIC GRAVITY**

A 6.8 kg block of some unknown material is suspended from a spring scale and submerged in water. The spring scale reads 48.0 N. What is the specific gravity of the block?

*April 25, 2016*

**science**

H2SO4 is labeled 93.2% and density 1.94g/cm3. Find moles in H2SO4?

*April 24, 2016*

**Chemistry**

Hello Dr. Bob, I see the mistake that I have made, but the initial values that were in my first sentence were given, I just think my coefficients in the equation were wrong. Do the answers at the bottom make sense though?

*April 23, 2016*

**Chemistry**

A flask initially contains 2.00 atm of NH3, 2.00 atm of N2, and 3.00 atm of H2 at 673 Kelvin. -What is the delta G for the reaction? -What is the equilibrium partial pressures of each gas at 673 Kelvin? So I figured out how to do the first question with relevant values: : ...

*April 23, 2016*

**Algebra**

7 – 5(2 – x) = –(x – 8) = 11/6

*April 19, 2016*

**Math**

Evaluate: -17 + 6 =

*April 19, 2016*

**math**

Lines a and b are parallel. When they are cut by transversals, they form a triangle. es025-1.jpg What is es025-2.jpg es025-3.jpg

*April 19, 2016*

**Chem**

Given the equation 2C8H18 + 25O2 = 16 CO2 + 18H2O: How many moles of oxygen gas (O2) are consumed upon combustion of 2.20 L of octane ( D = 0.703 g/mL)?

*April 10, 2016*

**Work**

A truck carrying a 57 kg crate accelerates uniformly from rest to 86.5 km/hr in 18.4 s. Calculate the work done on the crate by the truck (in J). I got 16454 J right. Now why is it positive? K-K = negative if Velocity from rest is 0.

*April 10, 2016*

**Block Colliding with a Spring**

I think there something wrong with the quiz, cuz it tells me its wrong. I tried 3.75N (work by spring) and also total work done. It shouldnt be, I got the 2 other questions right. Still, thank you.

*April 10, 2016*

**Block Colliding with a Spring**

A moving 1.60 kg block collides with a horizontal spring whose spring constant is 480 N/m. The block compresses the spring a maximum distance of 12.50 cm from its rest position. The coefficient of kinetic friction between the block and the horizontal surface is 0.480. What is ...

*April 10, 2016*

**PHYSICS CENTER OF MASS**

what is the .065??? same for y .065???

*April 10, 2016*

**chemistry**

A radionuclide undergoes alpha emission, and thorium-234 is produced. What was the original radionuclide?

*April 7, 2016*

**math**

Can you plz do callbck for 0799998736&0742239920 then i will call u as soon as i can to tell u anything about careers

*April 7, 2016*

**Math**

A student takes a true-false test exam with 10 questions. If the student guesses all ten questions, find the probability he gets 7 or 8 right. p(x=7) + p(x=8) (.5)^7(.5)^3 + (.5)^8(.5)^2 I have the correct answers which are .117+.044= .161 But when I calculate the answer on ...

*March 30, 2016*

**Chemistry**

A single dose of a certain antacid contains 250. mg of Mg(OH)2 and 300. mg of CaCO3. How many mmol of H+ can be neutralized by one dose of this antacid? Do not include units in your answer

*March 29, 2016*

**math**

the product of a number and five decreased by eight

*March 29, 2016*

**math**

use the unit circle to determine the exact value of each angle: sine 30 degrees, cosine pi, sine 11 pi divided by 6, and cosine 135 degrees.

*March 28, 2016*

**math**

find the values of cosine 21 degrees, and sine 3 pi divided by 10

*March 28, 2016*

**math**

The Washington monument is 555 feet high. If you are standing one quarter of a mile, or 1320 feet, from the base of the monument and looking at the top, find the angle of elevation to the nearest degree.

*March 28, 2016*

**math**

At a certain time of the day the elevation of the sun is 40 degrees. To the nearest foot, find the height of a tree whose shadow is 35 feet long.

*March 28, 2016*

**Math troubles**

I calculated them on my calculator so I borrowed my friends (since mine was messing up). I got P(x=3) = 5C3 .25^3 .75^2 = 0.008 P(x=4) = 5C4 .25^4 .75^1 = 0.003 P(x=5) = 5C5 .25^5 .75^0 = 0.0007 added up =0.01. Did I calculate correctly

*March 27, 2016*

**Math troubles**

There's 5 multiple choice questions on a quiz. Four choices to each question. Find the probability that the student gets 3 or more questions right. p(x=3) (.25)^3= 0.015 p(x=4) (.25)^4=3.906 p(x=5) (.25)^5=9.765 Do you add them all together to get the overall probability?

*March 27, 2016*

**Statistics**

There's 5 multiple choice questions on a quiz. Four choices to each question. Find the probability that the student gets 3 or more questions right. p(x=3) (.25)^3= 0.015 p(x=4) (.25)^4=3.906 p(x=5) (.25)^5=9.765 Do you add them all together to get the overall probability?

*March 27, 2016*

**Social Studies PLS HELP!!!**

Jury duty is A: a right because it is discussed in the u.s constitution B: a right because only some citizens are required to do it C: A responsibility because citizens do it to help protect other's rights D: A responsibility because judges cannot make decisions without ...

*March 24, 2016*

**math**

a nut mixture is made from two types of nuts: one type selling for 7.50/kg the other selling for 9.50/kg what mass of each type of nut should ne included in a 3 kg mixture that sells for 25

*March 24, 2016*

**Chemistry**

Using the Table of Thermodynamic Data calculate Kp at 500 K for the reaction 2 HI(g)-->I2(g) + H2(g) , if Kp at 300 K is 2.16x10-3 , assuming that delta H˚ is constant.

*March 23, 2016*

**Chemistry**

The Kp for the production of phosgene is 18.0. If one mole each of CO and Cl2 are mixed at the total pressure of 1 atm, what will be the partial pressure (in atm) of COCl2 after equilibrium is reached, CO(g) + Cl2(g)-->COCl2(g)

*March 23, 2016*

**Chemistry**

What is the entropy change of liquid glycol (in cal K-1 mol-1 ) when it freezes at -25 ˚C?the heat of fusion of glycol is 2688 cal mol-1 , and the specific heats of liquid and solid glycol are 33.8 and 20.1 cal K-1 mol-1 , respectively.

*March 23, 2016*

**Maths**

The probability a pupil takes a bus to school is 0.3. If a sample of 10 pupils are chosen at random. Using binomial distribution. Find the probability that a) exactly four pupils travel by bus. b) more than six pupils travel by bus.

*March 20, 2016*

**ratios/algebra**

During class elections 64 students voted for candidate A .if the ratio of votes for candidate a is to the votes for candidate B was 8:5,how many votes did candidate B receive?

*March 14, 2016*

**Science**

Heat ice from 20 to 32= 6BTUx5lb=30 Melt Ice at 32=144x5lb=720 Change temp of water from 32to160=128x5LB=640 30+720+640=1390 Correct? I think I got it. Thanks for the help. Cleared a lot of things up.

*March 13, 2016*

**Science**

How many Btu's are required to change five pounds of ice at 20°F to water at 160°F? a. 2,608 Btu’s b. 1,390 Btu’s c. 1,304 Btu’s d. 141 Btu’s I am trying ((160-20)x.5)x5 but not getting any of the possible choices. What am I missing? Thanks for ...

*March 13, 2016*

**Maths**

A drawer contains 8 brown socks and 4 black socks. A sock is taken a random from the drawer, its colour noted and replaced. This is done three times. If X is the discrete variable, the number of brown socks taken. Draw the probability distribution of X.

*March 13, 2016*

**statistics**

Case Study Chapter 6 and 7 FOR FULL CREDIT SHOW EQUATIONS USED AND WORK. ELEVATOR CAPACITY: Suppose an elevator has a maximum capacity of 16 passengers with a total weight of 2500 lbs. The mean weight of females is less than the mean weight of males so we will only look at ...

*March 7, 2016*

**Math**

need direction on part c. Rosa and her friend build & paint a tree house. On monday they paint 2/5 of the tree house. On tuesday they paint 3/7 of the house. A - painting of the house need to be finished on wednesday. how much more work do they have to do? 14/35 + 15/35=29/35 ...

*February 29, 2016*

**physics**

Calculate the heat given off by the hot water. GIVEN: Original quantity of water (hot water) 50g Orig.temperature :40°C Final temperature: 9°C Final quantity of water: 264g Increase in quantity of water 214g. PLEASE KINDLY SHOW ME THE EQUATION FOR THIS THANK YOU. <3

*February 28, 2016*

**physics**

Calculate the heat given off by the hot water. GIVEN: Original quantity of water (hot water) 50g Orig.temperature :40°C Final temperature: 9°C Final quantity of water: 264g Increase in quantity of water 214g. PLEASE KINDLY SHOW ME THE EQUATION FOR THIS THANK YOU. <3

*February 28, 2016*

**physics**

Calculate the heat given off by the hot water. GIVEN: Original quantity of water (hot water) 50g Orig.temperature :40°C Final temperature: 9°C Final quantity of water: 264g Increase in quantity of water 214g. PLEASE KINDLY SHOW ME THE EQUATION FOR THIS THANK YOU. <3

*February 28, 2016*

**physics**

Calculate the heat given off by the hot water. GIVEN: Original quantity of water (hot water) 50g Orig.temperature :40°C Final temperature: 9°C Final quantity of water: 264g Increase in quantity of water 214g. PLEASE KINDLY SHOW ME THE EQUATION FOR THIS THANK YOU. <3

*February 28, 2016*

**microeconomics**

4.00 or less .

*February 27, 2016*

**N/A**

The most basic software required for an online course where writing is involved is:

*February 23, 2016*

**Chemistry**

How many mL of 1.2 M HCl is needed to react with 5.8 g of Al(OH)3

*February 18, 2016*

**science**

A feather is dropped on the moon from a height of 1.40meters.The acceleration of gravity on the moon is 1.67m/s^2.Determine the time for the feather to fall to the surface of the moon.

*February 18, 2016*

**Math**

Kathy is y years old Find her age,if 1/2 of wat she was 3 years ago is equal to 1/3 of what she will be in 4 years time

*February 16, 2016*

**Assessment**

Authentic and performance assessments strive for greater realism and complexity of tasks under the premise that real-life problems can often be solved ______________.

*February 14, 2016*

**Math**

If Sam has 6 apples and Linda takes 12 apples how many apples does Jesica have?

*February 9, 2016*

**Trigonometric**

A woman standing on a hill sees a flagpole that she knows is 55 ft tall. The angle of depression to the bottom of the pole is 14°, and the angle of elevation to the top of the pole is 18°. Find her distance x from the pole.

*February 7, 2016*

**Physics**

A bat moving at 5 meters per second is chasing a flying insect, if the bat emits a 40 khz chirp and receives back an echo at 40.4 khz what is the speed of the insect and will the bat be able to catch the insect?

*February 2, 2016*

**Math**

I got A and B but i need C Suppose a ship is sailing at a rate of 35km/h parellel to a straight shoreline. The ship is 10km from shore when it passes a lighthouse at 11am. a) Let k be the distance between the lighthouse and the ship. Let d be the distance from the ship has ...

*February 1, 2016*

**Math**

I got A and B but i need C Suppose a ship is sailing at a rate of 35km/h parellel to a straight shoreline. The ship is 10km from shore when it passes a lighthouse at 11am. Question 6 a) Let k be the distance between the lighthouse and the ship. Let d be the distance from the ...

*February 1, 2016*

**COMP1**

Heading back to the states but on edge since he survived the tsunami FRAGMENT OR NO

*January 31, 2016*

**Math**

wait I'm confused with c what do i do or put

*January 27, 2016*

**Math**

So b) i would just say d=35km *t

*January 27, 2016*

**Math**

Thank you guys both of you!

*January 27, 2016*

**Math**

Someone answer all of this clearly, I don't get it at all. Suppose a ship is sailing at a rate of 35km/h parellel to a straight shoreline. The ship is 10km from shore when it passes a lighthouse at 11am. Question 6 options: a) Let k be the distance between the lighthouse ...

*January 27, 2016*

**Science**

A tank which is raised above the ground level, has a hole in its flat base, through which water flows and falls to the ground below. If the depth of water in the tank is 0.5 m and the tank base is 0.7 m above the ground, what is the fluid velocity (u) (m/s) just before it ...

*January 27, 2016*

**Math**

Someone answer all of this clearly, I don't get it at all. Suppose a ship is sailing at a rate of 35km/h parellel to a straight shoreline. The ship is 10km from shore when it passes a lighthouse at 11am. Question 6 options: a) Let k be the distance between the lighthouse ...

*January 26, 2016*

**Math**

whats the composite function of these two equations and its domain and range f(x)=2^x and g(x)=3-x

*January 25, 2016*

**Math**

The answer is 306.

*January 25, 2016*

**Math**

Can you explain or show me how to do this problem: Mary bought 8 1/2 yards of ribbon. How many inches did she buy?

*January 25, 2016*

**chemistry**

How much energy is absorbed to change 7.25 g of ice at -3 C to 25.5C?

*January 25, 2016*

**Math**

Edit for g(x) i mean g(x)=3-x

*January 25, 2016*

**Math**

How about this idk if im right for this part F(x)=2^x g(x)=y-x

*January 25, 2016*

**Math**

What is the composite function of 3x^2-5x+6 and x^2+3x and what is its domain and range

*January 25, 2016*

**Math**

Help me for this question on composite functions Does the composition of functions display the commutative property? Give an example of each case to illustrate your answer.

*January 24, 2016*

**Math**

If a1,a2,…,a100 are real numbers such that a1=1 and a100=.01, evaluate ∑(j=1 to 99) (aj−aj+1).

*January 14, 2016*

**Math**

Finding the composite function

*January 13, 2016*

**Math**

Question 1 A) f(x)=2^x and g(x)=3−x I got 3x^2+12 don't know if im right B) i need help for this f(x)=sinx and g(x)=x

*January 13, 2016*

**Math**

We need help putting these fractions from greatest to least 2/3 3/4 1/2 8/10

*January 12, 2016*

**Math**

When I convert 400 quarts to 4000 Cups would the answer be 400 qt= 1600 cups and 4000 C < 400 qt?

*January 10, 2016*

**Math**

is the answer 4000 cups < 400 quarts because 400 quarts= 1600 Cups? Is it right?

*January 10, 2016*

**Math**

i have this so far 8=-8cos(pi/30(0-y))+8

*January 6, 2016*

**Math**

the value

*January 6, 2016*

**Math**

how can i solve for y value with this equation f(x)=-8cos(pi/30(x-y))+8

*January 6, 2016*

**Math**

Change the cos function into a sin function d(t)= -8cos (pi(t)/30)+8

*January 6, 2016*

**Math**

i mean the y value,change it to sin function

*January 6, 2016*

**Math**

Solve for d D(t)= -8cos (pi(t)/30)+8

*January 6, 2016*

**Math**

solve for d i mean

*January 5, 2016*

**Math**

Error I mean for d

*January 5, 2016*

**Math**

how do i solve for t and turn this equation into a sin function d(t)=-8cos(pi(t)/30)+8

*January 5, 2016*

**Math**

For each of the functions below, state the domain and range, the restrictions, the intervals of increasing and decreasing, the roots, y-intercepts, and vertices. a) f(x)=2x(^2)−8 b) f(x)=+√x-2

*January 3, 2016*

**English 3**

A verb must agree with its subject in number

*January 3, 2016*

**Math Exponetial Function Problem Question?**

Thank you so much damon!!

*January 2, 2016*

**Math Exponetial Function Problem Question?**

Im confused if im doing this right Last week there was an earthquake that measured as a magnitude of 3.2 on the Richter scale. Today you hear on the radio that there was a second earthquake that was 27 times more intense than the first. What was the magnitude of the second ...

*January 2, 2016*

**Math**

*86.4 i mean

*January 2, 2016*

**Math**

Are you sure this is right,someone told me since to get magmitude of the second i have to multiply 27 by first earthquake which is 3.2 27(3.2)=84 Im confused

*January 2, 2016*

**Math**

Ok,thanks!

*January 2, 2016*

**Math**

solve for x using logarithms round your answer to four decimal places. a)2^2x+3=80

*January 2, 2016*

**Math**

So i guess my answer is acceptable right :)

*January 2, 2016*

**Math**

For a)

*January 2, 2016*

**Math**

Okay i was wondering because some people told me the answer is log(f(x))=2xlog(3)

*January 2, 2016*