The CRC Handbook, a large reference book of chemical and physical data, lists two isotopes of europium (). The atomic mass of 47.81% of europium atoms is 150.920 u. Through a typographical oversight, the atomic mass of the second isotope is not printed. Calculate that atomic mass, taking the tabulated atomic mass of europium as 151.964 u.

Which supports the idea that birds and butterflies both have wings but they do not have a common ancestor with wings? a. the wings are analogous structures that evolved differently and do not have a similar internal structure. b. the wings are homologous structures that evolved differently and do not have a similar internal structure. c. wings of birds are vestigial structures, but the wing structures of bats are not vestigial. d. wings of bats are vestigial structures, but the wing structures of birds are not vestigial

What must happen before a body cell can begin mitotic cell division

Needthe meter is the standard unit for: 1) height 2) length 3) weight 4) mass