Why is glass or chinaware packed with straw?

$(i)$ Name the property by virtue of which a body resists a change in its state of motion. Name the physical quantity which is a measure of this property.
$(ii)$ Explain why some of the leaves may get detached from a tree if we vigorously shake its branch.

Two forces $F_{1} = 20 \, N$ and $F_{2} = 30 \, N$ are acting on an object in opposite directions as shown in the figure.
$(i)$ What is the net force acting on the object?
$(ii)$ What is the direction of the net force acting on the object?
$(iii)$ If the mass of the body is $10 \, kg$,what will be the acceleration produced in it?

Name and state the action and reaction in the following cases:
$(i)$ Firing of a bullet from a gun.
$(ii)$ Hammering a nail.
$(iii)$ $A$ book lying on a table.
$(iv)$ Moving rocket.
$(v)$ $A$ person moving on the floor.
$(vi)$ $A$ moving train colliding with a stationary train.

$A$ girl of mass $50 \, kg$ jumps out of a moving boat of mass $300 \, kg$ onto the bank with a horizontal velocity of $3 \, m s^{-1}$. With what velocity will the boat begin to move backwards (in $, m s^{-1}$)?

Which would require a greater force $-$ accelerating a $2 \ kg$ mass at $5 \ m s^{-2}$ or a $5 \ kg$ mass at $3 \ m s^{-2}$?