Correct Answer: D. Suffocation

Correct Answer: A) HNO3

Correct Answer: B. onto

Explanation

The function \(y = g(x)\) is one- to- one but \(z = h(y)\) is not one- to- one but onto.

\(\therefore h(g(x)) = onto\)

Correct Answer: A. high quality grass

Correct Answer: B. Inadequate supply of labour

Explanation

Inadequate supply of labour is not a problem facing the Economic Community of West African States (ECOWAS). ECOWAS is a regional economic community of 15 countries in West Africa. The countries in ECOWAS share a common goal of economic integration, and they have made significant progress in this area. However, there are still some challenges that the community faces, including language barriers, production of the same commodities, and poor transportation and communication. Inadequate supply of labour is not one of the challenges facing ECOWAS. In fact, the region has a large and growing labor force. This is due to the high population growth rates in many of the ECOWAS countries. The labour force is also relatively young, which means that there is a large pool of potential workers.

Explanation

(a) \(\log_{10} x + \log_{10} y = 4 ... (1)\)

\(\log_{10} x + 2 \log_{10} y = 3 ...(2)\)

\((1) \implies \log_{10} (xy) = 4 \therefore xy = 10^{4} ... (3)\)

\((2) \implies \log_{10} (xy^{2}) = 3 \therefore xy^{2} = 10^{3} ... (4)\)

Divide (4) by (3) :

\(y = 10^{-1} = 0.1\)

Put y in (3), we have

\(\frac{x}{10} = 10^{4} \implies x = 10^{5}\)

\((x, y) = (10^{5}, 10^{-1})\)

(b) (i) \(t \propto \frac{V}{P}\)

\(t = \frac{kV}{P}\)

when t = 10, V = 20 and P = 5.

\(10 = \frac{20k}{5} \implies 50 = 20k\)

\(k = \frac{5}{2}\)

\(\therefore t = \frac{5V}{2P}\)

(ii) When V = 50, P = 2, we have

\(t = \frac{5(50)}{2(2)} = \frac{250}{4}\)

= \(62.5 minutes\)

(iii) when V = 40, t = 20 minutes

\(20 = \frac{5(40)}{2P} \implies 40P = 200\)

\(P = \frac{200}{40} = 5 pumps\)

Correct Answer: D. Drilling

Correct Answer: B. It loses its magnetism readily

Correct Answer: A) chromatography

Correct Answer: A. 2, 8, 1