What is the minimum number of forces acting in the same plane on a particle that can result in a zero net force?

$A$ mass $M \text{ kg}$ is suspended by a weightless string. The horizontal force required to hold the mass at $60^{\circ}$ with the vertical is

As shown in the figure,a $70\,kg$ garden roller is pushed with a force of $\overrightarrow{F} = 200\,N$ at an angle of $30^{\circ}$ with the horizontal. The normal reaction on the roller is $.......\,N$ (Given $g = 10\,m s^{-2}$)

$A$ mass '$M$' is suspended by a rope from a rigid support at point '$P$' as shown in the figure. Another rope is tied at end '$Q$' and pulled horizontally with a force '$F$'. If the rope makes an angle '$\theta$' with the vertical,then the tension in the string '$PQ$' is

$A$ book is lying on a table. What is the angle between the normal reaction acting on the book on the table and the weight of the book (in $^\circ$)?

$A$ book of mass $5 \,kg$ is placed on a table and it is pressed by $10 \,N$ force. Then,the normal force exerted by the table on the book is ......... $N$.