Answer:
1 kg, 0.8 kg, 1.6 kg
Explanation:
Add up each part in the ratio
5 + 4 + 8 = 17
Divide the mass of the alloy by 17
3.4/17 = 0.2
To find out how much of each metal is in the alloy multiply 0.2kg by how many parts of it are in the alloy.
Nickel - 5 parts
0.2 x 5 = 1 kg
Zinc - 4 parts
0.2 x 4 = 0.8 kg
Copper - 8 parts
0.2 x 8 = 1.6 kg