Science & Mathematics - 18 February 2007

please tell me before i try it myself.

2007-02-18 16:37:32 · 19 answers · asked by Orange Juice 2 in Engineering

2007-02-18 16:36:29 · 6 answers · asked by Anonymous in Physics

Solve the following system of linear inequalities by graphing. Show your tests for shading. 3x + 4y ≤ 12 x + 3y ≤ 6 x ≥ 0 y ≥ 0

2007-02-18 16:32:56 · 5 answers · asked by sittinncat 1 in Mathematics

When you stick, let's say, a worm in the microwave, why does it blow up?

2007-02-18 16:32:15 · 6 answers · asked by Malice 1 in Physics

Please explain.

#1
A purchase is made under the following conditions. There is a 25% discount due to sale, another 10% discount because of the size of the purchase, and a 3% discount for paying cash. These discounts are successive. The customer paid $195.89. What was the original price before any discounts were considered?

2.Between twelve' o'clock midnight and twelve' o'clock noon, how many times are the minute hand and hour hand of a clock at right angles to each other?

2007-02-18 16:31:49 · 8 answers · asked by Anonymous in Mathematics

I need to index a permutation of 6 objects, and I need a relatively closed form expression (not a recursive function).
i.e. here is the first few permutations, and their associated index:
Index .....Permutation
1.............123456
2.............123465
3.............123546
4.............123564
5.............124356
etc.
I need a formula or algorithm that for a given index it will return the permutation.
So, in the example, for an index 4, the algorithm/function will return a '1' for the first digit, a '2' for the second, '3' for third, '5' for fourth etc.
Note: it need not follow the above example pattern - it just has to be such that all possible permutations are uniquely indexable.

2007-02-18 16:31:40 · 3 answers · asked by seasnowsky 2 in Mathematics

Solve the system by substitution. 2x + 2y = 0
y = 4x + 0

2007-02-18 16:29:38 · 11 answers · asked by sittinncat 1 in Mathematics

y= (e^-x + 1)/ e^x

cos^ -1 (6x/5)

cos^ -1 (3x^2 +2)

y = 3sin^-1 (5x^4)

log^15 (8 + ln15)

i really need help. thank you

2007-02-18 16:28:57 · 2 answers · asked by jayray0538 1 in Mathematics

2007-02-18 16:27:33 · 6 answers · asked by ghostrecon47 1 in Geography

I came across the following question on an IQ test, the answer to which I was left guessing on, after several minutes trying to solve it (non-mathematically):
Water is dripping into an empty glass. Each minute, the number of drops doubles. The glass is full in one hour. How many minutes does it take to fill the glass up to half?

a. 30 minutes
b. 40 minutes
c. 59 minutes
d. 1 minute
e. 23 minutes

It is worth noting that by doubling the drops, one arrives at very large number very quickly (ie:starting at one and doubling for 10 minutes gave me a value of 512 drops, if my math was correct! This is geometric progression). I ruled out letter a, because filling the last half would be done faster, given the mathematical progression. Likewise, letters d&e are ruled out, since either answer would assume that more time would be needed to fill the last half, which, again, as noted is not possible. This, then, only leaves letters b&c. Does this reasoning seem correct thus far?

2007-02-18 16:27:21 · 6 answers · asked by franco_american1962 2 in Mathematics

a recipe plz

2007-02-18 16:26:24 · 4 answers · asked by fat bastard 2 in Biology

Colud u please show me how u find the answer?

2007-02-18 16:26:11 · 2 answers · asked by john 1 in Mathematics

tropical pools sells an aboveground model of P dollars each. The monthly revenue from the sale of this model is given by
R = -0.08p^2 + 300p

Revenue is the product of the price p and the demand (quantity sold)

a) Factor out the price on the right-hand side of the formula.
B) What is an expression for the monthly demand?
C) What is the monthly demand for this pool when the price is $3000.
D) Estimate the price at which the revenue is maximized. Approximately how many pools will be sold monthly at this price?
E) what is the approximate maximum revenue?

2007-02-18 16:24:21 · 1 answers · asked by Anonymous in Mathematics

2007-02-18 16:23:00 · 3 answers · asked by Kamala P 1 in Engineering

ya things like that, just tell me anything that nasa is making.

2007-02-18 16:22:44 · 5 answers · asked by Anonymous in Astronomy & Space

2007-02-18 16:22:04 · 7 answers · asked by elvis 1 in Earth Sciences & Geology

e^2x+1

2007-02-18 16:21:36 · 3 answers · asked by Tavis T 1 in Mathematics

who could give a deeper explanation about zero and undefined slope?
why is a vertical line an undefined slope?
ex.
we have 0 on the y axis and 4 on the x axis.
that means it's (4, 0) but that's only one point.
we need 2 points or more to create a line
if we try to compute the slope (without other points)
then it is 0/4 which is zero not undefined.

***
what are the other points in that vertical line so that we could have a line?
who could provide a deeper explanation?

2007-02-18 16:21:31 · 5 answers · asked by jiarenqu 1 in Mathematics

what are the sounds of the invironment that are related to these intensities : 0dB SPL,10 dB SPL,30 dB SPL,60 dB SPL,90 dB SPL,140 dB SPL ??

2007-02-18 16:20:49 · 1 answers · asked by Anonymous in Other - Science

Please explain your answer

#1
At some stops, a certain bus picks up 5 people. At other stops, it picks up 2 and, at the same time, lets for of five. There are no other stops but these. It starts its run empty and picks up five people. At the end, it has 11 people aboard. If the number of stops is greater than 17, what is the least number of stops the bus makes?

#2 On a string of 33 pearls, the middle pearl is the largest and the most expensive of all. Starting from one end, each pearl is worth $100 more than the one before, up to the middle. From the other end, each pearl is worth $150 more than the one before, up to the middle. The string of pearls is worth $65,000. What is the value of the middle pearl?

#3
Suppose it takes 3.25 miles along a highway to go from an altitude of 5,000 feet to altitude of 6000 feet. What is the percent grade? (the grade of a highway is the vertical rise in distance divided by the change in horizontal distance for the rise)

2007-02-18 16:20:11 · 4 answers · asked by Anonymous in Mathematics

I have a small area in the backyard to work with, it gets morning and afternoon sun but I live along the coast. I would like one that doesn't get too big. Thanks!

2007-02-18 16:18:47 · 1 answers · asked by lina 1 in Botany

2h^2 - h - 3 = 0

2007-02-18 16:13:43 · 4 answers · asked by Anonymous in Mathematics

Solve the system by addition.–5x + 2y = 10
x – 3y = 11

2007-02-18 16:11:43 · 6 answers · asked by sittinncat 1 in Mathematics

Why do some objects have certern colours while others don't.

2007-02-18 16:11:34 · 7 answers · asked by Unazaki 4 in Physics

2007-02-18 16:10:43 · 5 answers · asked by Stanley C 1 in Zoology

2007-02-18 16:10:25 · 5 answers · asked by Ichigo 4 in Zoology

m^3 + 2m^2 - 3m = 0

2007-02-18 16:08:56 · 3 answers · asked by I can help 1 in Mathematics

2007-02-18 16:08:39 · 2 answers · asked by Alisha B 1 in Chemistry

Does a human body have gravity? Any sources will be appreciated.

2007-02-18 16:08:13 · 5 answers · asked by Anonymous in Physics

A car is traveling on a road that is perpendicular to a railroad track.. When the car is 30 meters from the crossing, the car's new collision detector warns the driver there is a train 50 meters from the car and heading toward the same crossing. How far is the train from the crossing?

2007-02-18 16:08:00 · 3 answers · asked by I can help 1 in Mathematics