The element Durkium has two isotopes, durkium-18 with a mass of 17.812 amu and durkium-22 with a mass of 21.546. Durkium is made up of 44.52% of durkium-18 and 55.48% of durkium-22. What|is the average atomic mass of durkium?

Which statements are true concerning mineral formation? check all that apply. the slower the cooling, the larger the crystals. the faster the cooling, the smaller the crystals. crystals formed from magma are smaller than crystals formed from lava. minerals can only form in solutions when the solution is heated deep underground. when a solution cools, elements and compounds leave the solution and crystallize as minerals. minerals formed from hot water solutions can form narrow channels in the surrounding rock.