Joe and grace are baking cookie

Which pair of angles are vertical angles? ∠1 and ∠4 ∠1 and ∠2 ∠2 and ∠4 ∠2 and ∠3

When y’all answer can y’all explain too !

Serena is making an experiment. for that, she needs 20 grams of a 52% solution of salt. she has two large bottles of salt water: one with 40% and the other with 70% of salt in them. how much of each must she use to make the solution she needs? i am in need of