Help me please.

Zoe is investigating the composition of substance a, an unknown substance. using chemical processes, she analyzes substance a and determines it is composed of sodium, oxygen, and hydrogen atoms in a ratio of 1 : 1 : 1. what is substance a? a. a compound b. an element c. a heterogeneous mixture d. a homogeneous mixture

How many miles of water are produced if 5.43 mol pbo2 are consumed

Drug abuse will not lead to physical and psychological dependence. true or false ?