Please help.

Asample of radium-226 will decay 1/4 of its original amount after 3200years. what is the half-life of radium-226?

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.

What statement goes against the kinetic theory of gases