Correct Answer: D. Antarctic drift

Correct Answer: D. A-horizon

Explanation

rakah starts with Takbiratul-Ihram pronounced with both hands raised to the ear level and followed by the recitation of Suratul- Fatihah and a surah or ayat.This is immediately followed by the ruku posture where subhana Rabiyyal Azim is pronounced; standing posture with samiallahu liman hamidah and Rabbana lakal- hamd upon standing erect. After this, the worshipper goes to the sujud posture with feet, knees, hands, forehead and the nose touching the ground and saying of Subhana Rabbiyal Ala.He then makes a short sitting and returns to the sujud posture with the same utterance as for the first one. This marks the end of a unit of prayer (Salat).

Correct Answer: B. Iodine crystals molecules are held together by weak forces

Explanation

The correct answer is B. Iodine crystals molecules are held together by weak forces.

Here's why:

• Sublimation is the direct change from a solid to a gas without passing through a liquid phase. Iodine sublimes because the forces holding the individual iodine molecules (I2) together in the crystal lattice are relatively weak.

• A. Iodine crystals sublime: This describes *what* happens, not *why* it happens.

• B. Iodine crystals molecules are held together by weak forces: Iodine (I2) is a molecular solid. The forces *between* the I2 molecules are London Dispersion Forces, which are a type of van der Waals force. While these forces are present in all molecular substances, they are relatively weak compared to ionic bonds or covalent bonds. When heated, only a small amount of energy is needed to overcome these weak intermolecular forces, allowing the molecules to escape directly into the gaseous state.

• C. Iodine atoms are held together by strong forces: This refers to the strong covalent bond *within* an I2 molecule (intra-molecular forces). These bonds are not broken during a phase change; the molecules themselves remain intact. Phase changes involve overcoming the forces *between* molecules.

• D. Iodine molecules are covalent: While true that iodine molecules are covalent (I-I bond), this statement alone doesn't explain sublimation. Many covalent substances have high melting and boiling points (e.g., diamond, silicon dioxide). The *type* of intermolecular forces (which are weak in iodine due to its nonpolar nature) is the key factor.

Therefore, the weak intermolecular forces (London Dispersion Forces) between the iodine molecules are the reason why iodine crystals sublime readily when heated.

Correct Answer: A. gnesis

Explanation

Gnesis is a metamorphic rock. Metamorphic rocks are formed from pre-existing rocks which have been changed as a result of great heat and pressure

Correct Answer: C. the supremacy of the ordinary law

Correct Answer: B. 7.1A

Correct Answer: C. Mower

Correct Answer: C. 200ms^-1

Explanation

In strings, \(\lambda\) = 2L

V = F\(\lambda\)

= 200 x 2 x 0.5

= 200ms^-1

Correct Answer: A. is tested