Is what happening in the air or the atmosphere at one time in one place

The period of a pendulum varies directly as the square root of the length of the pendulum and inversely as the square root of the acceleration due to gravity. find the period when the length is 144 cm and the acceleration due to gravity is 980 cm per second squared, if the period is 7pi seconds when the length is 289 cm and the acceleration due to gravity is 980 cm per second squared.

Select all the correct answers. which three statements about electromagnetic radiation are true?

Acid precipitation chemically weathering a 5.0-kg limestone rock . which coukd be the result ?