Which best describes why projectiles move in a curved path? They have constant horizontal velocity and vertical acceleration.
They have horizontal acceleration and vertical momentum.
They have horizontal acceleration and constant vertical velocity.
They have horizontal momentum and constant vertical velocity.

What is the temperature of one mole of helium gas at stp?

As air becomes more dense, (select all that apply) o. air weighs less o. gas molecules are closer together o. air is colder o. air weighs more o. gas molecules are further apart o. air is hotter

Which statement is true about hcl? (5 points) select one: a. it is a salt because it increases the concentration of metallic ions. b. it is a salt because it is formed by the reaction of an acid and a base. c. it is an acid because it increases the concentration of hydroxyl ions. d. it is an acid because it increases the concentration of hydronium ions.