 
 <translate> A. 13 (can be weighed by keeping weights of 10, 2 and 4 )
B. 15 (cannot be weighed)
C. 17 (can be weighed by keeping weights of 10 and 7 kg)
D. 19(can be weighed by keeping weights of 10, 2 and 7 kg)
E. 21 (can be weighed by keeping weights of 10, 7 and 4 kg) So the final answer is (B). <hau> A. 13 (ana iya auna shi ta hanyar kiyaye nauyin 10, 2 da 4) B. 15 (ba za a iya auna shi ba) C. 17 (ana iya auna shi ta hanyar riƙe nauyin 10 da 7 kg) D. 19 ((za a iya auna ta hanyar riƙe nauyin 10, 2 da 7 kg) E. 21 (ana iya auna shi ta hanyar riƙe nauyin 10, 7 da 4 kg) Don haka amsar ƙarshe ita ce (B). 