How many main types of muscles are there?

The value of the series $\cos 12^{\circ} + \cos 84^{\circ} + \cos 132^{\circ} + \cos 156^{\circ}$ is

Assuming the sun to be a spherical body of radius $R$ at a temperature of $T \ K$,evaluate the total radiant power incident on the earth at a distance $r$ from the sun. (Where $r_0$ is the radius of the earth and $\sigma$ is Stefan's constant.)

In the figure shown,the power generated in $y$ is maximum when $y = 5\,\Omega$. Then $R$ is .............. $\Omega$.

Which of the following elements has the highest reaction rate with water?

Which of the following has the highest electropositive character?