Answer:
The system of equation that represent this situations are;

Also 5 hats and 10 scarves can be prepared from 2 kg of yarn.
Step-by-step explanation:
Let number of hat Chevy makes be h.
Also Let number of scarves Chevy makes be s.
Given:
Total Amount of yarns = 2 kg
Total number of items = 15
Since Items need to make are hat and scarves.
Hence the equation can be represented as;

Again Given:
Each hat uses 0.2 kilograms of yarn.
each scarf uses 0.1 kilograms of yarn.
Hence the equation can be represented as;

Hence the system of equation that represent this situations are;

Now Solving these to find number of hats and number of scarves.
Multiplying equation 2 with 10 we get;

Now Subtracting equation 1 from equation 3 we get;

Now Substituting the value of h in equation 1 we get;

Hence 5 hats and 10 scarves can be prepared from 2 kg of yarn.