Explain why some solar eclipses are total and some are annular.

Some solar are eclipse are total and some are annular because the eclipse are not a total circle so, at the different phase of year the moon and the sun are away from the earth at different degree.

Every occurring eclipse of sun are not considered as total solar eclipse. The moon are sometimes too small for covering the entire disk of the sun. And the annular eclipse are only happen when the moon covers the entire area of the sun.    

the answer is mosques. they are an important part of islamic culture.

electromagnetic shielding is the practice of reducing the electromagnetic field in a space by blocking the field with barriers made of conductive or magnetic materials. shielding is typically applied to enclosures to isolate electrical devices from their surroundings, and to cables to isolate wires from the environment through which the cable runs. electromagnetic shielding that blocks radio frequency electromagnetic radiation is also known as rf shielding.

the shielding can reduce the coupling of radio waves, electromagnetic fields and electrostatic fields. a conductive enclosure used to block electrostatic fields is also known as a faraday cage. the amount of reduction depends very much upon the material used, its thickness, the size of the shielded volume and the frequency of the fields of interest and the size, shape and orientation of apertures in a shield to an incident electromagnetic

from wikipedia