Science & Mathematics - 18 January 2007

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Solve for x: x^2+7x+4=0 If the solutions are complex numbers then give your solutions in the usual a+bi form?

thank you so much

2007-01-18 01:20:38 · 4 answers · asked by pkbrauer 1 in Mathematics

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help!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!?

i really tried this,
1. a train running at a uniform speed passes a bridge 275m long in 15 seconds and another bridge 425m long in 21 secs. find
1. the lenght of the train.
2. the speed of the train in km\hour.
ans=100m and 90km/hour

2. the speed of a boat in still water is 10km per hour. if the boat goes 37.5 kms upstream in 5hrs find the speed of the stream.
ans=2.5km/hour

3.the speed of a boat in still water is 9km/hr; if the boat goes 54 km down stream in 4hrs find the speed pf the stream.
ans=4.5km/hour

the formulae for speed is speed=distance/time.
hints for Q1. distance travelled by train= length of the train + length of the platform.
to convert km/hr to metre/ sec 5/18
and to convert metre/second to km/hr 18/5.

Q2. if the speed of a boat in the still water= x
and the speed of stream = y
then, the speed of boat in the irection opposite to the current(up stream)= x-y
and the speed of boat in the direction to the current = x+y.
pls help!

2007-01-18 01:19:01 · 4 answers · asked by Anonymous in Mathematics

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What is your opinion about John Titor and Ethan Titor?

Are those guys fakers?

2007-01-18 01:18:23 · 4 answers · asked by noname 1 in Astronomy & Space

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Badger v Fox?

what creature would win in a straight fight?

2007-01-18 01:16:26 · 20 answers · asked by Anonymous in Zoology

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Why does the sun turn black when I take a picture of it?

2007-01-18 01:14:05 · 2 answers · asked by Sarah . 1 in Astronomy & Space

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Which one is greater 300! or 100^300?

I have tried it myself but the proof is very large. Any simple and sensible solution will be highly appreciated.

2007-01-18 01:11:45 · 12 answers · asked by Anonymous in Mathematics

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How do you perform CPR?

And is it possible to break any bones like the sternum or a rib? Has this ever happened?

2007-01-18 01:10:49 · 13 answers · asked by Melissa S 5 in Medicine

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genetic, reasoning?

a study is undertaken to determine the nature of a mutant allele of the "G gene" Many families in which both parents have the genotyepe Gg are found, and their children are genotyped. the researchers found 65 children with a Gg genotype, 35 children with GG genotype, and 0 children with gg genotype
how can you explain this abnormal ratio?

2007-01-18 01:10:43 · 5 answers · asked by smile 1 in Biology

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Solve for x: x^2-6x+9=0. If the solution are complex numbers then give your solutions in the usual a+bi form?

2007-01-18 01:08:09 · 5 answers · asked by pkbrauer 1 in Mathematics

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Humans have eight different blood types. How many and what blood types do cows have?

2007-01-18 01:07:00 · 3 answers · asked by ari-pup 7 in Biology

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What is mean by incremental encoder, absolute encoder, singleturn encoder and multiturn encoder?

2007-01-18 01:05:20 · 3 answers · asked by krish s 1 in Engineering

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Are we(Indians)really independent?

2007-01-18 01:04:42 · 10 answers · asked by moulana 2 in Engineering

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Where can I buy hundreds of nonlethal spiders inexpensively?

I have a coworker who hates spiders, and I would like to release an unholy number of them in his company vehicle. Using tarantulas would be effective, but costly.

Where can I buy generic, run-of-the-mill spiders in bulk in the United States? Are they ever used as feed for pets? Please keep in mind, I do not wish to kill my coworker, just scare the everloving bejeezus out of him.

2007-01-18 01:04:13 · 5 answers · asked by ? 5 in Zoology

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