Superintendence, direction, and control of elections to

Which statement about the properties of light and sound is incorrect? 

What is the SI unit of G — the universal gravitation constant?

What type of image is always formed by a convex mirror?

With reference to the types of electromagnetic waves, consider the following statements:

What conditions must be met for stationary waves to form?

Velocity of the sound is minimum in-

The device used for locating submerged objects under sea is –

Smog is a combination of –

Why does a solid chunk of iron float in mercury but sink in water?

What is the device used to amplify and modulate microwave frequency signals called?