euee biology 2014 from unit 1 variables
ባዮሎጅ የ case ጥያቄ ነው።


በጣም ቀላል ነው መልሱ control variable ነው።

🚩A control variable is anything that is held constant or limited in a research study. It’s a variable that is not of interest to the studies objectives , but is controlled because it could influence the outcomes.

🚩A dependent variable is what you measure in the experiment and what is affected during the experiment. The dependent variable responds to the independent variable. It is called dependent because it "depends" on the independent variable

🚩An independent variable is exactly what it sounds like. It is a variable that stands alone and isn't changed by the other variables you are trying to measure. For example, someone's age might be an independent variable.

🚩Confounding variables are those that affect other variables in a way that produces spurious or distorted associations between two variables. They confound the "true" relationship between two variables.

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ለጥያቄዎቹ  መልስ

1,Correct answer: B
[H3O+]=5∗10−10M
Explanation:
An acidic solution will always have a hydronium concentration greater than 1∗10−7M. A basic solution will always have a hydroxide concentration greater than 1∗10−7M. If the hydroxide concentration is equal to the hydronium concentration, the solution is neutral.
The opposite of the above conditions can also be noted. If the hydronium concentration is less than 1∗10−7M, then the solution will be basic. An example of this is a solution where the hydronium ion concentration is 5∗10−10M. Since this value is far less than 1∗10−7M, this will be a basic solution.

2.Correct answer: A
Lewis acid

Explanation:
There are three principle definitions for acids and bases.

The Arrhenius definition is the simplest, and states that acids are compounds that increase proton concentration in solution, while bases are compounds that increase hydroxide concentration in solution. Arrhenius acids will always contain hydrogen and Arrhenius bases will always contain hydroxide groups.

Brønsted-Lowry definitions center on proton donation. Brønsted-Lowry acids are species that donate protons, and Brønsted-Lowry bases are compounds that accept protons.

Lewis acids and bases refer to the donation or acceptance of an electron pair. Lewis bases donate an electron pair, and Lewis acids accept an electron pair.

3,Correct answer: A
A strong acid

Explanation:
Strong acids and bases dissociate completely into ions when placed in an aqueous solution. In contrast, weak acids and bases do not completely dissociate.

There are only six strong acids: perchloric acid (HClO4), hydroiodic acid (HI), hydrobromic acid (HBr), hydrochloric acid (HCl), nitric acid (HNO3), and sulfuric acid (H2SO4).

4,Correct answer: C
Brønsted-Lowry acids are proton donors when dissolved in water

Explanation:
There are three primary classifications of acids and bases.

Arrhenius acids yield protons when dissolved in solution, while Arrhenius bases yield hydroxide ions.

Brønsted-Lowry acids are protone donors, while Brønsted-Lowry bases are proton acceptors.

Lewis acids are electron acceptors, while Lewis bases are electron donors.

An acid that dissociates completely in solution is considered a strong acid due to its high Ka value.

5,Correct answer: B
donates a pair of electrons to a Lewis acid

Explanation:
The most common Lewis bases are anions, and therefore, have unpaired valence electrons which may be donated to Lewis acids. The concept of donating and/or accepting hydrogens refers to the Bronsted-Lowry definition of acids. A Bronsted-Lowry acid donates hydrogens.

6,Correct answer: C
(aq)

Explanation:
Acids are soluble in water substance, but remember, only water gets the liquid (l) phase label. Since acids are almost always dissolved in water, we use the (aq) subscript at the end of the chemical formula to indicate its phase.

7,Correct answer: D
electron pair acceptors

Explanation:
According to the Lewis definition, acids are electron pair acceptors.

8,Correct answer: D .Brønsted-Lowry electron pair donors

Explanation:
According to the Lewis definition, bases are electron pair donors.

9,Correct answer: D
A substance can act either as an acid or a base

Explanation:
An amphoteric substance is one that can act either as an acid or a base. Amino acids are good examples of amphoteric substances; they have a carboxylic acid group that can be acidic, and an amino group that can be basic.

10,Correct answer:C
An acid with 2 ionizable hydrogens

Explanation:
Acids have hydrogen ions and balanced charges, "di" tells us that the acid in question has two potential hydrogen ions, which can be ionized and turned into protons (protic). These acids, like H2SO4 can ionize once, yielding HSO−4+H+ then again, yielding SO2−4+H+.

English EUEE 🙋QUESTION

The collapsed building ___ three fire-fighters.

❤️ kill

🤩 kills

👍 killed

🔥 killing

React to right ✅answer

ዛሬ በ EXAM PACKAGE ማትስ ሞዴል ፈተና ላይ 19 አምጥቶ በ 2 ወር ልዩነት ውስጥ ኢንትራነስ ላይ 76 እንዴት ማምጣት እንደቻለ አንድ ተማሪ ይነግረናል!!!

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🌻Chapter 9🌻

✈️Trigonometric functions ✈️

ሰላም ውዶቸ ክለሳ እንዴት ይዟችኋል ። chapter 2 ስናይ እንደመግቢያ ያክል አይተነዋል graph ,domain, range ወዘተ የመሳሰሉትን ማለት ነው ።ዛሬ ደግሞ

🚩inverse of trigonometric functions
🚩graphs of some trigonometric functions
🚩solutions of trigonometric equations
🚩applications of trigonometric functions

እናያለን አብራችሁን ቆዩ ።

🌷In mathematics, the inverse trigonometric functions are the inverse functions of the trigonometric functions. Specifically, they are the inverses of the sine, cosine, tangent, cotangent, secant, and cosecant functions, and are used to obtain an angle from any of the angle's trigonometric ratios. 

🏆Trigonometric functions are periodic, therefore each range value is within the limitless domain values (no breaks in between). Since trigonometric functions have no restrictions, there is no inverse.

🤽ማወቅ ያለብን inverse እንዲኖር የግድ የ domain limit ያስፈልጋል ።

🏅Arcsine is the inverse of sine function. It is used to evaluate the angle whose sine value is equal to the ratio of its opposite side and hypotenuse.

🏅arccosine is the inverse function of the cosine function. This means that they are opposite functions, and one will cancel out the other. The arccosine is mainly used to determine the measure of an angle when two sides of a right triangle are known.

🏅arctan is the inverse of the tangent function and is used to compute the angle measure from the tangent ratio (tan = opposite/adjacent) of a right triangle. Arctan can be calculated in terms of degrees and as well as radians.

🏅ArcCsc is the inverse cosecant function. For a real number , ArcCsc[x] represents the radian angle measure 

🏅arcsec. the inverse function of the secant; the angle that has a secant equal to a given number. synonyms: arc secant, arcsecant, inverse secant. type of: circular function, trigonometric function.

የእያንዳንዱን domain and range እና graph ምን እንደሚመስል ከፎቶው ላይ ማግኘት ትችላላችሁ ።

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