What is the simplified value of the numerical expression A = (3/4 - 1/6) / (5/12)?
Mathematics
Question · Easy
The houseplant does both
Short
Which of the following is the scientific notation of the number 0.000408?
What is the simplified form of √75 - 2√12 + √27?
Question · Medium
Expand and simplify the algebraic expression (2x - 3)^2 - (2x + 1)(2x - 1).
Question · Hard
What is the solution in ℝ of the linear equation 3(2x - 5) - 4(x - 2) = 7?
Solve the system of linear equations in ℝ × ℝ: { 2x + 3y = 12 ; 3x - y = 7 }.
Which interval represents the set of solutions in ℝ to the inequality -3x + 5 ≤ -4?
A right triangle ABC is right-angled at A. If AB = 6 cm and AC = 8 cm, what is the length of hypotenuse BC?
In triangle ABC, point M lies on [AB] and N on [AC] such that line (MN) is parallel to (BC). If AM = 3 cm, AB = 9 cm, and AN = 4 cm, what is the length of segment AC?
In a right-angled triangle ABC with hypotenuse BC = 13 cm and adjacent side AB = 5 cm to angle B, what is the exact value of cos(B)?
What is the area of a trapezoid with bases of length b1 = 8 cm and b2 = 14 cm, and height h = 6 cm?
Points A(2, -1) and B(6, 3) are plotted in an orthonormal coordinate system (O, I, J). What are the coordinates of the midpoint M of segment [AB]?
What is the Euclidean distance between points P(1, 2) and Q(4, 6) in an orthonormal coordinate plane?
If vector u has coordinates (3, -2) and vector v has coordinates (-1, 4), what are the coordinates of the vector w = 2u + 3v?
In a circle with center O, an inscribed angle BAC intercepts arc BC. If the central angle BOC intercepting the same arc measures 76°, what is the measure of angle BAC?
Consider the statistical data set of marks obtained by 9 students: 8, 10, 11, 12, 12, 14, 15, 17, 19. What is the median mark?
A bag contains 5 red balls, 3 blue balls, and 2 green balls, all identical in size and shape. One ball is drawn at random. What is the probability of drawing a blue ball?
For a narrative composition about a difficult journey, which opening most effectively establishes a setting and an immediate problem?
Composition
Which outline best supports the thesis 'Community libraries deserve public support because they expand access to knowledge'?
Which transition best completes this paragraph? 'The first seedlings failed during the dry spell. ___, the group changed its watering schedule and the second planting survived.'
Which sentence functions as evidence rather than as the thesis of an argumentative composition?
Which revision most effectively replaces the vague description 'The market was very busy' with concrete sensory detail?
A paragraph argues that school gardens teach practical science. Which sentence should be removed to preserve paragraph unity?
Which sequence gives the clearest chronology for a narrative paragraph?
Which conclusion best completes an essay arguing that communities should protect local water sources?
What physical quantity is measured in newtons (N) in the International System of Units (SI)?
Physical Sciences
A solid object has a mass of 450 g and occupies a volume of 50 cm^3. What is its density (masse volumique)?
On Earth, where gravitational acceleration g ≈ 10 N/kg, what is the weight of an object with a mass of 25 kg?
A vehicle travels a distance of 180 km in 2 hours and 30 minutes at constant speed. What is its average speed in km/h?
According to Ohm's law, what is the electric current flowing through a resistor of R = 20 Ω connected across a potential difference of U = 12 V?
Two resistors of resistances R1 = 30 Ω and R2 = 60 Ω are connected in parallel. What is their equivalent resistance Req?
An electrical appliance with a power rating of 1,500 W operates for 4 hours. How much electrical energy does it consume in kilowatt-hours (kWh)?
Which formula represents sulfuric acid, the diprotic acid commonly written with two ionizable hydrogen atoms?
In the complete combustion of methane (CH4) in oxygen (O2), what are the two chemical products formed?
A sample of pure water is neutral at 25 °C. What pH should it have under those conditions?
Which gas turns limewater (eau de chaux) milky/turbid, serving as its standard identification test?
What is the primary organ in the human body responsible for pumping blood through the circulatory system?
Natural Sciences
In green plants, what is the biological process by which light energy is converted into chemical energy (glucose) while absorbing carbon dioxide and releasing oxygen?
During circulation from the lungs to body tissues, which blood component carries most of the oxygen?
What is the causative agent of malaria (paludisme), which is transmitted to humans through the bite of an infected female Anopheles mosquito?
In the human digestive system, in which organ does the majority of nutrient absorption take place?
What is the fundamental law of reflection for a ray of light striking a smooth flat mirror?
Which of the following blood groups is considered the universal red blood cell donor in the ABO blood group system?
What is the primary environmental consequence of excessive deforestation and soil erosion in the Sahelian zone of Mali?
In classical genetics, when an individual possesses two identical alleles for a given gene (for example, BB or bb), the individual is said to be:
Which historic battle in 1235 saw Sundiata Keïta defeat the Sosso king Soumaoro Kanté, leading to the foundation of the Mali Empire?
History And Geography
Which famous emperor of Mali undertook a legendary pilgrimage to Mecca in 1324, distributing gold in Cairo and bringing Mediterranean scholars and architects back to Timbuktu?
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