Correct Answer: A. device in which the speaker means the opposite of what he says

Correct Answer: B. N28.00

Explanation

P = (80 x 5 + 100 x 3)8

= 5600W

Cost = \(\frac{5600}{1000} \times 5 = N28\)

Correct Answer: B. an industrial market

Correct Answer: B. 20 mol/dm³

Correct Answer: B. cation exchange

Correct Answer: D. 0 and -1

Explanation

\(\sqrt{x} + \sqrt{x + 1} = \sqrt{2x + 1}\)

Squaring both sides, we have

\((\sqrt{x} + \sqrt{x + 1})^{2} = (\sqrt{2x + 1})^{2}\)

\(x + 2\sqrt{x(x + 1)} + x + 1 = 2x + 1\)

\(2x + 1 + 2\sqrt{x(x+1)} - (2x + 1) = 0\)

\((2\sqrt{x(x + 1)})^{2}= 0^{2} \implies 4(x(x + 1)) = 0\)

\(\therefore x(x + 1) = 0\)

\(x = \text{0 or -1}\)

Correct Answer: A. bank charges

Correct Answer: D. \(\frac{56}{33}\)

Explanation

\(\tan (x + y) = \frac{\tan x + \tan y}{1 - \tan x\tan y}\)

\(\tan x = \frac{5}{12} ; \tan y = \frac{3}{4}\)

\(\tan (x + y) = \frac{\frac{5}{12} + \frac{3}{4}}{1 - (\frac{5}{12} \times \frac{3}{4}})\)

= \(\frac{\frac{14}{12}}{\frac{33}{48}}\)

= \(\frac{56}{33}\)

Correct Answer: B. positively sloped

Explanation

Ostentation goods are goods that are expensive such as jewelries, gold wrist watch etc. The higher the price, the higher the quantity demanded. Therefore, the relationship between price and quantity demanded is positive.

Correct Answer: C) Ahmadu Bello

Explanation

Ahmadu Bello was a Nigerian statesman who played a key role in Nigeria's struggle for independence from Britain. He was also the leader of the northern people's congress and served as the Premier of the Northern Region of Nigeria from 1954 until his assassination in 1966. He was a strong advocate for the development of the northern region and worked to ensure that the region received a fair share of Nigeria's resources.

Abubakar Tafawa Balewa was Nigeria's first prime minister and played a key role in the country's independence from Britain. Yakubu Maitama Sule was a Nigerian politician, diplomat and statesman who served as Nigeria's representative to the United Nations. Aminu Kano was a Nigerian politician and social reformer who was the founder of the Northern Elements Progressive Union (NEPU), which later merged with other parties to form the People's Redemption Party (PRP).

In summary, the correct answer to the question is option C, Ahmadu Bello, who was the leader of the northern people's congress and served as the Premier of the Northern Region of Nigeria from 1954 until his assassination in 1966.