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## Let p and q be distinct odd primes. Define $n=pq$ and$\phi(n)=(p−1)(q−1)$

(a) Show that $p+q = n−\phi(n)+1$ and $p−q = \sqrt{(p+q)^2−4n}$. ￼(b) Suppose you are given that $n = 675683$ and are told that $p−q = 2$. Explain how this information can help us factor

mathematics

## When ordering coffee, do you say "two milks" or "two milk"?

I've already searched the site if this question had been asked before however I didn't find anything related to my question. Every time I order coffee some people sort of correct me by saying

english-language

## What is the particle residence time for given flow rates of gas mixture components?

For two different chemical substances there are two open valves with flow rates $$Q_1=a\frac{m^3}{h}\ \text{ and }\ \ Q_2=b\frac{m^3}{h},$$ leading into seperate cables. Next, the cables join, the

physics

## Is there a better approximation of drag (other than quadratic drag)?

This is a student inquiry sparked by sheer curiosity. Wikipedia states the drag equation, $F = 1/2v^2pC_dA_c$. (p = mass density of fluid/gas, v = velocity, c_d = drag coefficient, a_c = cross

physics

## How do I calculate the distance a ship will take to stop?

I am a River Pilot and drive ships for a living. These ships are very large and range up to 160,000 Metric Tons. I am trying to figure out how to calculate the distance to stopping. I have a basic

physics

## How to estimate the Kolmogorov length scale

My understanding of Kolmogorov scales doesn't really go beyond this poem: Big whirls have little whirls that feed on their velocity, and little whirls have lesser whirls and so on to viscosity

physics

## How to construct this oracle quantum gate?

I was reading the paper Quantum Computational Complexity in the Presence of Closed Timelike Curves. In this the author mentions that following quantum oracle gate which operates on $n+1$ qubits, ca...

physics

## What is the expected target age for a YA (Young Adult) novel?

I'm curious about what the expected age for a YA young adult novel is, because it seems to have a huge range. Plus, the term YA seems terribly incorrect. I think most people believe these books are

writers

## Asking a question regarding prologue [on hold]

I have completed my book. But, stuck in the prologue section. The story is narrated by the writer instead of any character of the book. And, the main character dies in the end. Please suggest ...

writers

## [ Words in brackets in print and online]

Unfortunately I can't find a reference now, but many times I'll read an article either in print or online, and I'll see a certain word or phrase in brackets []. Here's a bad ex. The man walked up the

writers

## How do I show that two days has passed in a short story?

Ok so two days before my character is thinking about something and she is in her room. How do I show that two days later her friend is talking to her? Ok here are my rough sentences: She relaxed ...

writers

## Appositive phrase, participle phrase, gerund phrase and noun phrase. English is confusing

"Every English-speaking country is extremely sheepish towards mega-corporations and their puppet-governments. In continental Europe, France being an example, people stand up for their righ

english-language

## A classically trivial quantum field theory of electromagnetism

Presumably there is a field theory of electromagnetism that classically gives trivial equations of motion, but when quantized shows interesting topological phenomena. I am talking about the Lagrang...

physics

## '[sic]' to indicate punctuation errors

Can [sic] be used to highlight a punctuational error? In the sentence below, the bracketed sic would obviously denote that the punctuation preceding it was an error &mdash; that is, a semicolon

english-language

## Is the color wheel just an optical illusion?

As a kid, I was taught that that blue and yellow make green, yellow and red make orange, and red and blue make purple - forming the subtractive color wheel. As an adolescent I was taught that blue ...

physics

## Is it possible to reproduce the energy spectrum of quantum chaos using classical cellular automata?

Is it possible to reproduce the energy spectrum of quantum chaos using classical cellular automata? It's hardly impressive to reproduce harmonic oscillators.

physics

## Could we fly/drive through Jupiter?

If Jupiter is made of gas, could we fly or drive through it or would its center be too dense?

astronomy

## Is the white hole a myth or not?

I've been doing some research on white holes, and there has not been enough information to provide the answer. Some websites are saying that they might exist, but it is not yet proven. So, is it true

astronomy

## Are humans going to end up living in other planets?

Are humans going to live on something like Titan or not, in about 4 billion years (if they still exist then). If the sun is going to be expanding much bigger then, Earth will obviously heat up, so we

astronomy

## What would happen if a Black Hole and White Hole Collided?

Given our understanding of both black holes and white holes, what would be the outcome if they were both to suddenly collide? Black Holes: A black hole is a region of spacetime from which gravity

astronomy

## What are the main differences between solar flares and coronal mass ejections?

Specifically, what causes them, what sort of damage can they cause, and what are the differences in their composition?

astronomy

## How to calculate Kₚ from partial pressures at different temperatures?

At $25~^\circ\mathrm{C}$ and $1~\mathrm{atm}$, the partial pressures in an equilibrium mixture of $\ce{N2O4}$ and $\ce{NO2}$ are $0.7$ and $0.3$ respectively. Calculate their partial pressures ...

chemistry

## Absorbtion of light by a Coordination Compound

A $\ce{[M(H2O)6]^{2+}}$ complex typically absorbs at around $600$ nm. It is allowed to form a new complex $\ce{[M(NH3)6]^{2+}}$ that should have absorbtion at? The absorbtion is beacuse of transition

chemistry

## How to determine leftover substrates in sulfur and fluorine reaction? [on hold]

If 12 moles of fluorine gas are mixed with 5 moles of sulfur, how many moles of sulfur remain after 9 moles of fluorine react? A bit confusing to solve, given the following: \ce{S + 3F2 -> ...

chemistry

## Does bleach turn a substance white or colorless?

From what I understand, bleach works to weaken the ability of a substance to absorb light. Thus this seems to be "whitening" i.e. reflecting all light. In contrast, colorlessness (according to ...

chemistry