When is it clear that balanced forces are acting on an object

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

Which compound contain an iron with a 3+ charge

Ajet plane is speeding down the runway during takeoff. air resistance is not negligible. identify the forces on the jet.