An uncharged atom of calcium has an atomic number of 20 and an atomic mass of 43. How many electrons does calcium have?

How are extrusive rocks formed? magma gets trapped inside earth and cools to rock. volcanoes apply force to solid rocks and eject them. magma gets forced to earth’s surface and cools to rock. volcanoes trap lava inside earth, where it cools to rock.

If bacteria are much too small to see, what is one reason why can we see colonies in the petri dishes that have plenty of food to eat after only a few days?

According to your text, should be in the native language of the parents or guardians whenever possible. a. an email b. consent forms c. oral approval d. storybooks loaned out