Step 1. Analysis of Statement (I): - Viscosity is a measure of a fluid’s resistance to flow. Generally, liquids have higher viscosity than gases because of stronger intermolecular forces in liquids. Therefore, Statement (I) is incorrect.
Step 2. Analysis of Statement (II): - Surface tension is influenced by impurities. Insoluble impurities generally decrease the surface tension of a liquid by disrupting cohesive forces at the surface. Thus, Statement (II) is correct.
Since Statement I is incorrect and Statement II is correct, the correct answer is (2).
Let \( T_r \) be the \( r^{\text{th}} \) term of an A.P. If for some \( m \), \( T_m = \dfrac{1}{25} \), \( T_{25} = \dfrac{1}{20} \), and \( \displaystyle\sum_{r=1}^{25} T_r = 13 \), then \( 5m \displaystyle\sum_{r=m}^{2m} T_r \) is equal to: