Help me pls

The triangles are similar. what is the value of x? show your work.

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

£100.80 divided by 14 equals 7.2 how would we put this as money