Posts by DC

Total # Posts: 45

Maths
The projection of a line on axes are 6,2,3. What will the direction cosines of the lines be?

Maths
Here, P=Q-1 Now, P-Q = Q-1 - Q = -1 Therefore, P-Q=-1

Math
Multiply. write each product in simplest form. 3 7/10 X 7

math common core
1/4 pages typed per minute how many pages can be typed in 18minutes

Biology
ribosome structure

math
carmen is a girl scout camp counselor and needs to assign scouts to tents. She noticed that if two scouts were assigned to each tent then six girls would have no tent. On the other hand, if four scouts were assigned to each tent then there will be three empty tents how many ...

math
In a grand prix automobile race, Speedy Ryder averaged 110 miles per hour for the first half of the course and 130 miles per hour for the second half of the course. Cannonball Carter maintained a constant speed of 120 miles per hour throughout the race. Who won the race?

math
Tasha’s school bus usually drops her off in town every day at 4pm and her mother picks her up at the bus stop. Last Friday was a short school day, only Tasha’s mother forgot so she wasn’t at the bus stop when Tasha was dropped off an hour early, at 3pm. Since ...

math
two cars are approaching each other on the same highway one from san bernardino at 80 mph and the other from las vegas at 60 mph how far apart are they on the highway one hour before they meet?

math
The entire second grade at Sunshine Elementary participated in a single elimination checkers tournament. There are a total of 118 second graders and so there were 59 matches in the first round of the tournament. In the second round,the 59 remaining students were paired, ...

Math
azmin decided to get some exercise by taking the stairs from the first to the fifth floor in her apartment building. The first time she went up the entire flight, she walked up some steps and ran up 16 steps. This took a total of 60 seconds. The second time she went up the ...

Maths
10

geometry
If Dave is 6 feet tall and casts a shadow of 15 feet, what is the height of a tree that casts a shadow of 81 feet? Draw a diagram and solve for the height of the tree.

physics
A 34-kg girl is bouncing on a trampoline. During a certain interval after leaving the surface of the trampoline, her kinetic energy decreases to 220 J from 480 J. How high does she rise during this interval? Neglect air resistance.

Chemistry
ok I recalculated and got the w=.006523kJ and the energy change to be -76.82kJ... The energy change is right but the w is wrong for some reason... I calculated w as w=-delta(n)RT = -(0-.26312molO2)(8.314452x10^-2 Lbarr/molK)(25+273.15) = 6.5226J=.006523kJ...

Chemistry
help - confusion :( The oxidation of copper(I) oxide, Cu2O(s), to copper(II) oxide, CuO(s), is an exothermic process, 2 Cu2O + O2 --> 4CuO The change in enthalpy upon reaction of 75.30 g of Cu2O(s) is -76.83 kJ. Calculate the work, w, and energy change, ΔUrxn, when 75....

Chemistry
I would really appreciate some help with this thermochemistry problem! I'm really confused as to why I keep getting the wrong answers... I have gotten w=-1.305kj and energy change = 78.13kj... both of which were marked wrong. Here's the question: The oxidation of ...

Chemistry
Thanks Dr.Bob!! I was then able to plug into the second equation and found the concentration of calcium! You were great help! Thanks again :)

Chemistry
These are the given Ksp values to use: Ksp of Co(OH)2 is 5.9x10^-15 M^3 Ksp of Ca(OH)2 is 5.0x10^-6 M^3

Chemistry
A mineral sample is analyzed for its cobalt and calcium content. A sample is dissolved, and then the cobalt and calcium are precipitated as Co(OH)2(s) and Ca(OH)2(s). At what pH can Co(OH)2(s) be separated from Ca(OH)2(s) at 25 °C? Assume that an effective separation ...

Chemistry
A canister holds a gas at 16.3 psi when the temperature is 15˚C. To what will the pressure change when the temperature is increased to 20˚C? *

Chemistry
A canister holds a gas at 16.3 psi when the temperature is 15˚C. To what will the pressure change when the temperature is increased to 20˚C? *

Chemistry
10.7 L of a gas at 1.75 atm are expanded to 20.0 L at a constant temperature. What is the new gas pressure? *

Physics
,,,,,,

Math
Thank you Ms. Sue - Happy Holidays to you!

Math
(ACB)24

Math
Twelve people serve on a board and are considering three alternatives: A, B, and C. The choices followed by vote is shown in following table. Determine the winner, if any, using a Borda count. (ABC) 2 (ACB) 4 (BAC) 2 (BCA) 1 (CAB) 2 (CBA) 1 The winner is _____?

Algebra
You're awesome, thank you much and Happy Holidays to you!

Algebra
A club consists of 16 men and 19 women. In how many ways can they choose a president, vice president, treasurer, and secretary, along with an advisory committee of six people? (Round the answer to five decimal places.) _____ x 10(to the 11th power) ways

Algebra
You're awesome, thank you much and Happy Holidays to you!

Algebra
The campus vets club is having a raffle and is selling 2,700 tickets. If the people on your floor of the dorm bought 297 of those tickets, what is the probability that someone on your floor will hold the winning ticket? (Enter your answer as a decimal.)

Algebra
Thank you so much for your response. Just to be clear are you saying I need to multiply .8176 x 80 and then .7977 x 80?

Algebra
Suppose that people's heights (in centimeters) are normally distributed, with a mean of 175 and a standard deviation of 6. We find the heights of 80 people. (a) How many would you expect to be between 167 and 183 cm tall? (b) How many would you expect to be taller than 170...

physics
if i travel in a bus which have 40km/hour speed than i through a coin in vertical hight. Does the coin fall in my hand

living life a health life
what are the three methods by which HIV and AIDS are usually transmitted?

Math
x>55

Math
5w=42

college
Evaluate the difference quotient for the given function. Simplify your answer. f(x) = 3 + 5x − x2, f(4 + h) − f(4) h

LIfe orientation
5 ways : Water and sanition , Population

math
(9x^4+0x^3+8x^2+17x-20)÷(-3x-4)

math
The sum of the page numbers on the facing pages of a book is 457. Find the page numbers?