The question is based on microeconomics, please provide the required steps and the explanations! thank you very much

Question [4]: Let us consider Leontief preferences with demand function w a:(p,'w) = [min] . P1 +2172 1. Verify Cournot aggregation. 2. Verify Engel aggregation. 3. Suppose that the consumer has income of 20 and that the initial price vector is (p1, p2) = (2,2). Now let p1 change to 1. Find the total impact on the demand for good 1, and break it down into an income effect and a substitution effect (use Slutsky compensation.)