Plz help me in this question

Which of the following statement about pascal's triangle are true?

Ihave trouble finding the nth term of a linear sequence

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