$A$ 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 $^\circ$)?

$A$ body is at rest under the action of three forces,two of which are $\vec F_1 = 4\hat i$ and $\vec F_2 = 6\hat j$. The third force is:

Describe the different types of common forces.

$A$ flexible chain of mass $m$ hangs between two fixed points at the same level. The inclination of the chain with the horizontal at the two points of support is $30^{\circ}$. Considering the equilibrium of each half of the chain,the tension of the chain at the lowest point is . . . . . . .

Statement-$I$: If three forces $\vec{F}_{1}, \vec{F}_{2}$ and $\vec{F}_{3}$ are represented by three sides of a triangle and $\vec{F}_{1} + \vec{F}_{2} = -\vec{F}_{3}$,then these three forces are concurrent forces and satisfy the condition for equilibrium.
Statement-$II$: $A$ triangle made up of three forces $\vec{F}_{1}, \vec{F}_{2}$ and $\vec{F}_{3}$ as its sides taken in the same order,satisfy the condition for translatory equilibrium.
In the light of the above statements,choose the most appropriate answer from the options given below:

Find the magnitude of the unknown forces $x$ and $y$ if the sum of all forces is zero.