There are approximately 6 trillion miles in a light-year, so the distance we need to go is 6 trillion miles / light-year times. 4 light-years is equal to 24 trillion miles. So, this whole would take 1.2 billion hours. There are 24 hours a day and 365.25 days per year, so this time in years is 137 thousand years.

Answer: D) All the above Explanation: Intermolecular forces : The forces of attraction present in between the molecules or atoms or compounds is termed as intermolecular forces. The molecule HCl is composed of hydrogen and chlorine atom. There is high difference in electronegativities therefore, it is polar in nature. The H end of HCl is permanently slightly positive charge. The Cl end of HCl has a permanent slight negative charge. the "H" in one molecule is attracted to the "Cl" in a neighbor. The intermolecular force is weak compared to a covalent bond. But this dipole-dipole interaction is one of the stronger intermolecular attractions. It also has hydrogen bonding and dispersion forces.  Dispersion forces are the weakest forces which are present in between all molecules or atoms.Hydrogen bonds are present in molecules having at least one H-A bond where A is the strong electronegative atom (mainly F, Cl and N).

Answer: D) All the above Explanation: The Multiples of 18 are 18, 36, 54, 72, 90, 108, 126, ....   Multiples of 18 are nothing but numbers which are divisible by 18 leaving remainder 0.   An infinite number of multiples of 18 can be achieved by adding 18 to each subsequent multiple.

Answer: C) Rs. 20 Explanation: Let the Oranges be 'O', Bananas be 'B' and Apples be 'A' From the given data,   2O + 3B + 4A = 15 ...... (I) 3O + 2B + A = 10 ..... (II) On adding (I) and (II), 5O + 5B + 5A = 25 O + B + A = 5 4O + 4B + 4A = 20.

Answer: D) 3/8 Explanation: 3/4 divided by 2 = 3/4/2 = 3/4x2 = 3/8.   Hence, 3/4 divided by 2 is equal to 3/8.

Answer: A) CaO Explanation: An ionic bond is a chemical bond between two atoms in which one atom seems to donate its electron to another atom.   Here in the given compounds, the compound that contains ionic bond is CaO, Calcium oxide.

Answer: D) Both B & C Explanation: Distance between two Consecutive Crests or two Consecutive Troughs is called Wavelength. But the distance between crest and adjacent trough is half the wavelength. That is the distance between adjacent crest and trough is called Half the wavelength.

Answer: A) 5 Explanation: The following arrangements satisfy all 3 conditions. Arrangement 1: 3 books in a row; 12 rows. Arrangement 2: 4 books in a row; 9 rows.Arrangement 3: 6 books in a row; 6 rows.Arrangement 4: 9 books in a row; 4 rows.Arrangement 5: 12 books in a row; 3 rows.   Therefore, the possible arrangements are 5.