The mars rover curiosity has recently found evidence that there was liquid water on the planet’s surface at some point in its history. because we have not found any liquid water on the planet today, what does this imply about mars?

Simple astronomical telescope the objective lens has a focal length of 75 cm and that of a piece of 5cm of the lenses are 18 cm apart when will be final image of a distant object before

The us and canadian governments are doing all of the following to combat environmental problems except a. encouraging the use of public transportation b. enacting clean water policies c. requiring emissions testing d. limiting animal populations in some regions

Explain how earths tilt and revolution around the sun affects weather and climate