 
 <translate> Use some thinking to answer the following question. Which of the following CANNOT be weighed using a balance scale and these unit weights: 2, 4, 7, and 10
Options:
(A) 16
(B) 15
(C) 18
(D) 19
(E) 21 <ibo> Chebara ajụjụ na-esonụ echiche. Olee nke n'ime ihe ndị na-esonụ A PỤGHỊ iji ihe e ji atụ̀ ihe na-atụ n'ihe ma jiri ihe ndị a e ji atụ̀ ihe tụọ: 2, 4, 7, na 10 Nhọrọ: (A) 16 (B) 15 (C) 18 (D) 19 (E) 21 