In models of molecules, gray spheres are carbon atoms, white spheres are hydrogen atoms, red spheres are oxygen
atoms, and blue spheres are nitrogen atoms.
The chemical formula for hydrogen peroxide is H2O2. Which model
represents a molecule of hydrogen peroxide?

Two pans of a balance are 24.1 cm apart. the fulcrum of the balance has been shifted 1.33 cm away from the center by a dishonest shopkeeper. by what percentage is the true weight of the goods being marked up by the shopkeeper? assume the balance has negligible mass. answer in units of %.