Correct Answer: A. 3.0 seconds

Explanation

\(s = ut + \frac{1}{2}gt^{2}\)

\(u = 0; s = 45m; g = 10ms^{-2}\)

\(45 = 0 + \frac{1}{2}(10)t^{2} = 5t^{2}\)

\(t^{2} = \frac{45}{5} = 9\)

\(t = 3.0s\)

Correct Answer: D. \(ab^2 - a^2b\)

Explanation

\(\frac{a^2 b^4 - b^2 a^4}{ab(a + b)}\) = \(\frac{a^2 b^24(b^2 - a^2}{ab(a + b)}\)

= \(\frac{ab [(b - a) (b + a)]}{a + b}\)

= ab(b - a)

= \(ab^2 - a^2b\)

Correct Answer: B. inspiration from Allah

Correct Answer: B. clayey

Correct Answer: C. sound alike

Correct Answer: B. avoid doubtful things

Correct Answer: B) Average cost is at the minimum

Explanation

This question is about the relationship between average cost and marginal cost. Average cost is the total cost of producing a good or service, divided by the quantity produced. Marginal cost is the additional cost of producing one more unit of a good or service. The question asks when the average cost is equal to the marginal cost.

The correct answer is Option B: Average cost is at the minimum. When the average cost is at its minimum, it means that the cost of producing each additional unit is decreasing. This also means that the marginal cost is equal to the average cost at that point.

If the average cost is at the maximum (Option A), it means that the cost of producing each additional unit is increasing, so the marginal cost will be higher than the average cost. If the marginal cost is at the minimum (Option C), it means that the cost of producing one more unit is at its lowest point, but this does not necessarily mean that it is equal to the average cost. Finally, if the marginal cost is at the maximum (Option D), it means that the cost of producing one more unit is at its highest point, so it will be higher than the average cost.

Understanding the relationship between average cost and marginal cost is important in economics because it helps businesses determine the optimal level of production and pricing for their goods or services.

Correct Answer: D. electrons have moved to a higher energy level.

Explanation

An atom in an excited state is one whose electrons have moved to a higher energy level.

In an atom, electrons are typically found in specific energy levels or orbitals. When an electron absorbs energy, it can move from a lower energy level to a higher energy level, which is referred to as an excited state. In this higher energy state, the electron is farther from the nucleus and has more potential energy. When the electron returns to its lower energy level, it emits the excess energy as electromagnetic radiation, often in the form of visible light. This is what gives rise to the characteristic spectral lines observed in spectroscopy.

Correct Answer: B. shale

Correct Answer: D. 1.5V, 1Ω