A girl tries to lift a suitcase of weight $220 \mathrm{N}$ by pulling upwards on it with a force of $140 \mathrm{N}$. The suitcase does not move. Calculate the reaction force from the floor on the suitcase.

A block of mass $M$ is connected with a string to a smaller block of mass $m$. The big block is resting on a smooth inclined plane as shown in the diagram. Determine the angle of the plane in terms of $M$ and $m$ in order to have equilibrium.