Unit conversion - miles/h to metres/s

An object moves from position +34m to the position -15m in 15 seconds. what is the total displacement? what is the total velocity?

Considering only the earth's rotation, determine how much later the asteroid would have had to arrive to put the explosion above helsinki at longitude 25˚ e? this would have obliterated the city.

Which of the following statements are true for an isothermal process? check all that apply. - during an isothermal process, the work done by the gas equals the heat added to the gas. - during an isothermal process, the internal energy of the system changes. - an isothermal process is carried out at constant temperature. - an isothermal process is carried out at constant pressure. - an isothermal process is carried out at constant volume.