Acluster of atoms whose magnetic fields are aligned in the same direction is a magnetic

An electric power distributor charges residential customers $0.10 per kilowatt-hour (kwh). the company advertises that "green power" is available in 150 kwh blocks for an additional $4 per month. (green power is generated from solar, wind power, and methane sources.) if a certain customer uses an average of 391 kwh per month and commits to one monthly 150 kwh block of green power, what is her annual power bill

Abox is sliding on a frictionless surface when it suddenly begins to rain heavily. if the downpour of rainfall falls vertically into the box

Definition: this is the weighted average of all of the isotopes of an element.