Select the choice that translates the following verbal phrase correctly to algebra: the difference of m and 7 increased by 15

Each pair of clay balls represents two planetesimals. if each planetesimal is composed of the same material and is separated he the same distance, which pair experiences the frayed gravitational attraction?

The “ecological footprint” left by a citizen of a developed nation is about four times larger than that left by a citizen of a developing nation. why is this the case?

Ascientific idea becomes valid when it is what?