Identify the infinite sequence generated by the formula an =(-1)^n * 2^n

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

Express -5 2/5 as an improper fraction.

Point m is located at (-4, -6). what is located 4 units from point m? ( its on a coordinate plane by the way. )