Explanation

(a) Favourable Factors:

(i) Very high temperature

(ii) Dry areas (annual rainfall less than 75cm e.g Sokoto and Chad basin

(iii) Short wet saason (about 4 months)

(iv) Low humidity

(v) Development of large scale irrigation schemes e.g Tiga Dam, Kainji Dam

(vi) Presence of fertile alluvial soils e.g Niger basin

(b) Major farming areas and crops:

(i) Niger-Benu a river valley sugarcane, rice maize

(ii) Sokoto-Rima river valley rice, tobacco, cotton sweet potatoes, onion, groundnut

(iii) Chad basin wheat, millet, guinea corn, rice, cotton, onions,

(iv) Jebba and Kainja areas in the middle belt of Nigeria sugarcane rice:

(v) Gongola-Numan River Basin sugarcane rice, guinea corn etc.

(c) Problems:

(i) Flooding

(ii) Fluctuation in level of water

(iii) Displacement of settlements

(iv) Many dams disrupt normal flow of rivers

(iv) Possible accumulation of mineral salt e.g sodium

Correct Answer: C. cardiac muscles

Correct Answer: A. N6,150

Correct Answer: C. Import quota

Explanation

An import quota is a limit on the amount of goods that can be brought into a particular country. This means importers cannot exceed the quantity of imports permitted on the licence

Correct Answer: B. 24

Correct Answer: C. 0.30A

Explanation

Given Data: Emf = 1v, r = 2 ohms, R = 3 ohms, I = ?

3 resistance in parallel = \(\frac{1}{r_1}\) + \(\frac{1}{r_2}\) + \(\frac{1}{r_3}\)

\(\frac{1}{r_T}\)= \(\frac{1}{2}\) + \(\frac{1}{2}\) + \(\frac{1}{2}\)

\(\frac{1}{r_T}\) = \(\frac{1+1+1}{2}\)

\(\frac{1}{r_T}\) = \(\frac{3}{2}\)

cross multiply

r\(_T\) = \(\frac{2}{3}\) or 0.67

E = I(R+r)

1 = I(3+0.67)

1 = I(3.67)

1 ÷ 3.67 = I

0.27 = I

: I ≈ 0.30A

Correct Answer: B. Calcium oxide

Explanation

Ammonia (NH_3) is a basic gas. When choosing a drying agent for ammonia, it's crucial to select one that does not react with it.

Let's evaluate each option:

• A. Concentrated tetraoxonitrate (Vl) acid: This likely refers to concentrated nitric acid (HNO_3) or is a typo for concentrated sulfuric acid (H_2SO_4). Both are strong acids. Ammonia is a base, so it would react vigorously with either of these acids to form ammonium salts (e.g., NH_3 + HNO_3 \rightarrow NH_4NO_3). Therefore, concentrated acids cannot be used.

• B. Calcium oxide (CaO): Calcium oxide is a basic oxide. Since ammonia is also basic, there will be no acid-base reaction between them. Calcium oxide is an effective drying agent. Therefore, calcium oxide is suitable for drying ammonia gas.

• C. Anhydrous calcium chloride (CaCl_2): While anhydrous calcium chloride is a common and effective drying agent for many gases, it forms an addition compound (adduct) with ammonia, such as CaCl_2 \cdot 8NH_3. This means it will absorb the ammonia itself, not just the water, making it unsuitable for drying ammonia.

• D. Phosphorus (V) oxide (P_4O_{10} or P_2O_5): Phosphorus (V) oxide is an acidic oxide. It reacts with water to form phosphoric acid (H_3PO_4). Since ammonia is a base, it would react with the phosphoric acid formed (or directly with the oxide in the presence of water) to form ammonium phosphate. Therefore, phosphorus (V) oxide cannot be used.

Based on this analysis, calcium oxide is the only suitable drying agent for ammonia gas among the given options.

The final answer is B

Correct Answer: D. covalent bonds

Explanation

It's generally created using silicon, germanium, or other pure elements.

Semiconductors are created by adding impurities to the element.

The conductance or inductance of the element depends on the type and intensity of the added impurities.

The electrons surrounding each atom in a semiconductor are part of a covalent bond

Correct Answer: C. obeyed God's voice and kept His convenant

Correct Answer: D) 2.50 x 103N