Correct Answer: A. \(\frac{x - 7}{x^2 + x - 6}\)

Explanation

\(\frac{2}{x + 3} - \frac{1}{x - 2}\) = \(\frac{2(x - 2) - (x - 3)}{(x + 3) (x - 2)}\)

= \(\frac{2x - 4 - x - 3}{x^2 - 2x + 3x - 6}\)

= \(\frac{x -7}{x^2 + x - 6}\)

= \(\frac{x - 7}{x^2 + x - 6}\)

Correct Answer: B. 0.74 mol dm^-3

Explanation

Molar mass of Na2SO4 = 2(Na) + S + 4(O) = 2(23.0 g/mol) + 32.1 g/mol + 4(16.0 g/mol) = 46.0 g/mol + 32.1 g/mol + 64.0 g/mol = 142.1 g/mol

Now, we can calculate the number of moles of Na2SO4 in the solution:

Number of moles = Mass of the salt / Molar mass

Number of moles = 10.5 g / 142.1 g/mol ≈ 0.0739 mol

Next, we need to find the volume of the saturated solution, given as 100 cm³, and convert it to liters:

Volume of solution = 100 cm³ = 100 cm³ / 1000 cm³/dm³ = 0.1 dm³

Finally, we can calculate the solubility in mol/dm³:

Solubility = Number of moles / Volume of solution

Solubility = 0.0739 mol / 0.1 dm³ ≈ 0.739 mol/dm³

Rounded to two decimal places, the solubility of sodium tetraoxosulphate (VI) at 30°C is approximately 0.74 mol/dm³.

Therefore, the correct option is:

0.74 mol dm-3.

Solubility = 10.5 g / 100 cm3 * 142 g/mol = 0.739 mol/dm3

Correct Answer: C. Jeremiah

Correct Answer: D. giving alms to the poor

Explanation

1. Respect the Rights, Beliefs and Opinions of Others:
2. Stay Informed of the Issues That Affect Your Community:
3. Serve in a Jury When Called Upon:
4. Participate in the Democratic Process:
5. Defend the Country, if Need Should Arise:

Correct Answer: C. \(\frac{3}{5}\)

Explanation

prob(p) = \(\frac{1}{5}\)

prob(Q) = \(\frac{1}{4}\)

Prob(neither p) = 1 - \(\frac{1}{5}\)

\(\frac{5 - 1}{5} = \frac{4}{5}\)

prob(neither Q) = 1 - \(\frac{1}{4}\)

\(\frac{4 - 1}{4} = \frac{3}{4}\)

prob(neither of them) = \(\frac{4}{5} \times \frac{3}{4} = \frac{12}{20}\)

= \(\frac{3}{5}\)

Correct Answer: D. political power

Explanation

(a) Definition: Climate is the average weather condition of a place, measured over a long period of time (over 35 years). Importance of climate in agriculture are: (i) affects the duration of a cropping season (ii) determines the yield of crops and animals (iii) limits the types of crops/livestock to be grown or reared in an area (iv) vegetation distribution affects soil formation (v) affects the incidence of pests (vi) affects the incidence of diseases.

(b) Ways in which high rainfall affects agricultural production: (i) prolongs the cropping season (ii) increases the problem of plant diseases (iii) determines the type of crop to be grown (iv) increases the incidence of erosion/flooding (v) encourages thick forestation thus the incidence of pest e.g. tse-tse flies infestation (vi) encourages the growth of disease causing organisms (pathogens) (vii) increases leaching of plant nutrients/soil acidity (viii) it causes water logging in clayey soil (ix) determines the type of crops or livestock grown or reared i.e. distribution of crops and animals (x) encourages faster or rapid growth of weeds.

(c) Forms in which water exists in soil are: (i) capillary water (ii) hygroscopic water (iii) gravitational water.

(d) Ways through which soil water may be lost are: (i) surface run-off/erosion (ii) percolation/seepage (iii) evaporation (iv) transpiration

Correct Answer: B. opening stock

Correct Answer: D. C₅H₁₂

Correct Answer: C) muscles or glands which work in response to the stimulus received from the motor nerves

Explanation

This Biology question is testing your knowledge of effectors. Effectors are either muscles or glands that work in response to the stimulus received from the motor nerves. The correct answer to this question is option C. Muscles and glands are both types of effectors that work in response to the stimulus received from the motor nerves. Muscles are responsible for movement in the body, while glands produce and secrete hormones and other substances. It's important to understand the relationship between effectors and motor nerves. Motor nerves are responsible for carrying signals from the brain and spinal cord to the effectors, telling them to either contract or secrete a substance. This is how the body is able to carry out various actions and functions. Remember, effectors are not the same as efferent neurons, which are responsible for carrying signals from the brain and spinal cord to the muscles and glands. Therefore, option D is not the correct answer to this question. In summary, effectors are either muscles or glands that work in response to the stimulus received from the motor nerves. They are responsible for carrying out various functions in the body, such as movement and secretion of hormones.