Explanation area of rectangle garden=1500m² length  of garden=500m width=x area of rectangle = length *breadth =1500=500*x x=1500/500 x=3m SH5-9-2023

Explanation The backbone of DNA consists of alternating deoxyribose sugar and phosphate groups , linked by phosphodiester bonds. Key Information : Sugar-Phosphate Backbone : Provides structural stability to the DNA double helix. Directionality: 5’ (phosphate) to 3’ (sugar) orientation. Nitrogenous Bases (A, T, C, G) : Attached to the sugar but not part of the backbone. Form hydrogen bonds to create base pairs (A-T, C-G).

Explanation ASF Act 1975  came into effect, it repealed the  Airports Security Force Ordinance, 1975 ...................... ASF Pakistan The Airport Security Force (Pakistan) (ASF) is part of the  Aviation Division (Pakistan)  ASF  is responsible for protecting the  airports and the facilities  and the planes (on-ground or in-air). .....................  ASF act was repealed after the promulgation of Federal Investigation Agency  Act, 1974 The Pakistan Special Police Establishment,   1948, and The Special Police and Provincial Police (Amalgamation)  Order 1962   act was repealed after the promulgation of the Federal Investigation Agency Act, 1974

Explanation Nucleic acids (DNA/RNA) are present in: Nucleus : Contains genomic DNA (eukaryotic cells). Mitochondria : Have their own mtDNA (vital for energy production). Chloroplasts (in plants/algae): Contain cpDNA for photosynthesis-related functions.

Explanation The modern periodic table is arranged by increasing atomic number (number of protons). This arrangement resolves inconsistencies in earlier tables and groups elements with similar properties together.

Explanation ATP (Adenosine Triphosphate) is called the energy currency of the cell because it stores and provides energy for cellular activities. It releases energy when converted to ADP (Adenosine Diphosphate), which is then recycled back into ATP through cellular respiration.

Explanation Boyle’s Law describes the inverse relationship between the pressure (P) and volume (V) of a given mass of gas at constant temperature (isothermal conditions): P ∝ 1/V or PV = constant Key Points : Conditions : Fixed mass and temperature (no chemical reactions). Example : Compressing a syringe (volume ↓ → pressure ↑).

Explanation The increase in length (or volume) of solids when heated is specifically called thermal expansion . Key Information : Thermal Expansion : Occurs due to increased atomic vibrations with temperature. Linear expansion : Change in length (e.g., railroad tracks expanding in summer). Volumetric expansion : Change in 3D dimensions (e.g., mercury in thermometers).

Explanation Methane is the simplest of saturated hydrocarbons with a chemical formula CH4. It consists of four hydrogen atoms and one carbon atom. It is the simplest alkane .

Explanation The average age of six girls is  126 months .  =(120+124+123+130+130+129+130)/7 =(886)/7 =126 Sh5-9-2023