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Water Management: Conservation, Quality, and Sustainable Solutions

Classified in Geology

Written at on English with a size of 5.85 KB.

Understanding Earth's Water Resources

  • Approximately 71% of the Earth’s surface is covered by water.
  • 97.5% of this water is salt water.
  • 2.5% of Earth’s water is freshwater.
  • 70% of freshwater is locked up in glaciers and ice caps.
  • Only 0.3% of the Earth's total water is accessible for human and animal use through rivers, lakes, and underground aquifers.

The Hydrologic Cycle

The hydrologic cycle is powered by solar energy.

  • Evaporation and Transpiration: Move water into the atmosphere.
  • Condensation: Forms clouds.
  • Precipitation: Returns water to the ground (rain, snow, etc.).
  • Runoff: Brings water back into streams, rivers, lakes, and oceans.

Water Usage Statistics

  • USA (Drinking): 13 gallons (50 liters) per person.

Typical Daily Supply Needs:

  • USA: 115 to 182
... Continue reading "Water Management: Conservation, Quality, and Sustainable Solutions" »

French Revolution: Key Events, Figures, and Analysis

Classified in History

Written at on English with a size of 4.05 KB.

Historical Source Evaluation

Understanding Historical Source Evaluation

Timeline of Key Events (American & French Revolutions)

  • American War of Independence: 1775 - 1783 (French involvement)
  • Assembly of Notables: 22 Feb - 25 May 1787
  • Lit De Justice: 6 Aug 1787, 8 May 1788
  • Day of Tiles: 10 June 1788
  • Harvest Crisis: 1788
  • Pamphlet War: 1788-1789
  • Cahiers De Doléances: 1789 (List of grievances)
  • Rural Revolt: March 1789
  • Réveillon Riots: 27-28 April 1789
  • Estates-General: May 1789
  • Declaration of the National Assembly: 17 June 1789
  • Tennis Court Oath: 20 June 1789
  • Royal Session: 23 June 1789
  • Necker’s Dismissal: 11 July 1789
  • Fall of the Bastille: 14 July 1789
  • Municipal Revolutions: 13-17 July 1789
  • The Great Fear: 20 July - 6 Aug 1789
  • Night of 4 August: Abolition of
... Continue reading "French Revolution: Key Events, Figures, and Analysis" »

Digital Logic: Moore's Law, Logic Gates, and Number Systems

Classified in Computers

Written at on English with a size of 708.55 KB.

Lecture 1: Moore's Law

Moore's Law: The number of transistors on microchips doubles every two years.

Lecture 2: Logic Gates

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AND, OR, and NOT gates are universal.

Logic word problem steps:

Example: In a bank, there were four employees: the bank manager, assistant manager, teller, and the security guard. The bank has a single vault for the storage of their money. This vault was designed so that it needs four signals to open it. These four signals are from the bank manager, assistant manager, teller, and the security guard. For the vault to open, it needs the following conditions:

  1. No single employee can open the vault.
  2. It can be opened with three employees as long as one of them is the manager.
  3. It can be opened by the manager together with the assistant
... Continue reading "Digital Logic: Moore's Law, Logic Gates, and Number Systems" »

Mastering English Grammar: Passive Voice, Causative, and More

Classified in Medicine & Health

Written at on English with a size of 3.13 KB.

Passive Voice

  • Active: The secretary types the letter.
  • Passive: The letters are typed by the secretary.
  • Future Simple: Will type / Will be typed
  • Past Simple: Typed / Were typed
  • Modal: Can type / Can be typed
  • Present Continuous: Am/is/are being + past participle
  • Present Perfect Simple: Have / has been + past participle

Impersonal Voice

  1. It is thought/said/believed + that...
  2. Subject + is considered/thought/said + to be...

The Causative (get/have + object + verb 3rd form)

Often associated with professions. Changes depending on the verbal tenses.

Ex: The painters painted my house / I had my house painted by the painters.

Wish Clauses

  1. Wish + subject + past simple (about the future): Not reality, but you want it to happen. Ej: I wish I were a rich man.
  2. Wish + could
... Continue reading "Mastering English Grammar: Passive Voice, Causative, and More" »

Mastering Stacks, Deques, Trees, and Graph Data Structures

Classified in Computers

Written at on English with a size of 21.54 KB.

A stack is a fundamental data structure in computer science that follows the Last In, First Out (LIFO) principle. This means that the last element added to the stack is the first one to be removed. You can think of it like a stack of plates: you can only add or remove the top plate.

### Key Concepts of a Stack:

1. Basic Operations:
   - Push: This operation adds an element to the top of the stack.
   - Pop: This operation removes the element from the top of the stack and returns it.
   - Peek (or Top): This operation returns the top element of the stack without removing it.
   - IsEmpty: This operation checks whether the stack is empty.

2. Implementation:
   Stacks can be implemented using arrays or linked lists. Here are the details for... Continue reading "Mastering Stacks, Deques, Trees, and Graph Data Structures" »

Taxation of Income from Other Sources in India: Key Q&A

Classified in Economy

Written at on English with a size of 11.99 KB.

Income from Other Sources: Key Questions and Answers

Q1. What is the name of the fifth head of income?

Ans: Income from other sources.

Q2. What are the essential conditions for chargeability of income under the head 'Income from Other Sources'?

Ans: The following conditions must be satisfied:

  • (i) There must be an income that is not exempted from tax.
  • (ii) The income must not be chargeable under any of the first four heads (i.e., other than the head 'Income from Other Sources').

Q3. Write two examples of income that are chargeable under the head 'Income from Other Sources'.

Ans:

  • (i) Winning from lotteries
  • (ii) Winning from crossword puzzles

Q4. Under which head is the salary of MP/MLA charged?

Ans: Income from other sources.

Q5. Define the term 'security'

... Continue reading "Taxation of Income from Other Sources in India: Key Q&A" »

Essential Linux Commands: A Practical Reference

Classified in Computers

Written at on English with a size of 3.95 KB.

Essential Linux Commands

File and Directory Management

  • mkdir: Create a new directory.
  • ls: List contents of a directory.
  • rm: Remove files or directories (-r for recursive).
  • cp: Copy files or directories.
  • mv: Move or rename files or directories.
  • cat: Display file contents or create files.
  • less: View file contents one page at a time.
  • head: Display the first 10 lines of a file.
  • tail: Display the last 10 lines of a file.

System Information

  • uname: Show system information (kernel, version, etc.).
  • top: Display running processes and resource usage.
  • df: Show disk space usage.
  • df -h: Show disk usage in human-readable format.
  • free: Display memory usage (RAM and swap).

File Creation and Editing

  • touch: Create an empty file or update its timestamp.
  • echo: Write text to a file
... Continue reading "Essential Linux Commands: A Practical Reference" »

Essential Chemistry Definitions and Concepts

Classified in Chemistry

Written at on English with a size of 4.5 KB.

Essential Chemistry Definitions

Fundamental Concepts

  • Physical Property: Characteristics observed without changing the substance (color, melting point, density, boiling point).
  • Chemical Property: Characteristics observed when a substance changes into another (reactivity with air, acid, base, water, other chemicals).
  • Law of Conservation of Matter: Matter is neither created nor destroyed.
  • Atomic Theory: Theory of the nature of atoms.
  • Isotope: Atoms of the same element with different numbers of neutrons.
  • Ion: Atom or molecule with a net electric charge.
  • Cation: Positively charged ion.
  • Anion: Negatively charged ion.
  • Atomic Mass Unit (amu): Unit of mass for expressing atomic & molecular weights.
  • Mole: Unit for amount of substance (6.022 x 10^23 particles)
... Continue reading "Essential Chemistry Definitions and Concepts" »

Probability and Set Theory: Key Concepts and Formulas

Classified in Mathematics

Written at on English with a size of 621.25 KB.

De Morgan's Law

De Morgan's Law: (Flip if the union is true)

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Possible Outcomes and Probability Calculations

  • Repetition formula: nk
    • Example: 5 awards (k) and 30 students (n), with no limit to awards per student.
  • Permutation formula: P(n, k) = n! / (n - k)!
    • Example: Each student gets 1 award, so the number of students decreases by one each award.
  • No overlap probability: P(n, k) / repetition formula
  • Arrangements: a = slots → a! can be multiplied by arrangements within slots
  • Die sum probability:
    • List combinations that lead to the sum for each die.
    • If a die is rolled multiple times, each combination has (rolls)! permutations.
    • Add
... Continue reading "Probability and Set Theory: Key Concepts and Formulas" »

Human Body Systems: Excretion, Digestion, and Immunity

Classified in Biology

Written at on English with a size of 3.52 KB.

Human Body Systems and Excretion

Tissues/Organs/Organ System

Function in Excretion

Digestive System

Removal of faeces

Respiratory System

Removal of CO2 (alveoli)

Skin (sweat glands)

Removal of sweat and toxins

Urinary System

Blood filtration (Urine)

Absorption vs. Assimilation

Compare and contrast

Absorption and Assimilation

  • Similarity: Both involve nutrients—absorption transfers them into the bloodstream, and assimilation uses them in cells.

  • Difference: Absorption happens in the digestive system; assimilation occurs in tissues.

Digestion vs. Nutrition

Digestion and Nutrition

  • Similarity: Both are essential for energy and growth—digestion breaks down food, and nutrition provides the substances needed for this process.

  • Difference: Digestion is the physical

... Continue reading "Human Body Systems: Excretion, Digestion, and Immunity" »