Dung dịch được tạo ra do hòa tan 5gam chất tan X (không bay hơi, không điện li) trong 100 gam nước, bắt đầu đông đặc ở -1,550C. Nước có hằng số nghiệm đông là 1,86. Khối lượng phân tử của X là: A.46
B.58
C.60
D.74

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 can be found in the ionosphere

At element makes up all organic compounds?