You drive from your house to the dry cleaners, which is 12 miles east of your house. You then drive to the grocery store from the dry cleaners. The grocery store is 15 miles west of your house. You then drive back home from the grocery store. What was your displacement?

15 miles.

Explanation:

Displacement is the position you are in now relative to the position you were in when you started. If you had stopped at the dry cleaner's, your displacement would be 12 miles. However, you traveled back to your house and then 15 miles West of that, meaning you are now 15 miles away from your starting position.

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

find the surface area of the sphere to the nearest square unit. use a calculator.

a. 254 in.2

b. 64 in.2

c. 127 in.2

d. 1,018 in.2