A rhombus of side $20 \mathrm{cm}$ has two angles of $60°$ each. Find the length of the diagonals.

In the following figure $ABCD$ is a rectangle $DC=8 \mathrm{cm}$ and $BC=6 \mathrm{cm}$. Line segment $CM$ is drawn making an angle $30°$ with $DC,$ intersecting $AD$ with $M$. Find the length of $CM$ and $DM$.

Evaluate the following: 

$\frac{\sin 10°}{\cos 80°}$

Evaluate the following: 

$\frac{\cos 17°}{\sin 73°}$

Evaluate : $\frac{\tan 20°}{\cot 70°}$

Evaluate : $\frac{\sec 13°}{\mathrm{cosec}77°}$

Evaluate the following: 

$\frac{\mathrm{cosec}14°}{\sec 76°}$

Evaluate the following: 

$\sin 37°-\cos 53°$

Evaluate : $\tan 55°-\cot 35°$