Why liquid have a definite volume but no definite shape?

This is because the intermolecular forces are strong enough to hold the molecule together but not so strong as to fix them into definite positions (as in solids) instead, they possess fluidity and hence no definite shape.

Volume of a cylinder containing 10 marbles and gas is 1 litre at 2 atm pressure. Now pressure on the cylinder is increased to 4 atm, at which volume becomes 725 ml. Calculate volume of each marble.the

A gas occupied a volume of 250 ml at 700 mm Hg pressure and 25°C. What additional pressure is required to reduce the gas volume to its 4/5th value at the same temperature

A sample of a given mass of a gas at a constant temperature occupies 95cm3 under a pressure of 9.962 × 104N/m2 .At the same temperature, it volume at a pressure of 10.13 × 104 N/m2 is :

Calculate the mass of mercuryin a uniform column, 760 mm high and 1.00 cm2 in cross-sectional area. Is there any change in (a) mass and (b) pressure of column of same height but with 2.00 cm2 cross sectional area is taken ? (density of Hg = 13.6 g/cm3 )