Ответ:

N1:

84/100; 0.84; 84%

75/100; 0.75; 75%

13/25; 0.52; 52%

N2:

a) 54/100*30 = 16.2

b) 60/100*140 = 84

N3:

4/35*100 ≈ 11.429

N4:

1) 30/100*40 = 12

2) 30-12 = 18

B: 18

N5:

1) 28+40 = 68%

2) 100 - 68 = 32%

3) 1.2/32*100 = 3.75kg

B: 3.75kg