Aprojectile is launched with initial speed v and angle ? over level ground. the projectile's maximum height h and horizontal range d are related by the equation d = 1.8h, what was the launch angle of the projectile?

Which of the following correctly describes what happens when an atomic bomb explodes? small pieces of fissionable material are joined and form a body with a mass greater than the critical mass, the relative number of neutrons escaping decreases, and a chain reaction and explosion result. large pieces of fissionable matter are brought together quickly and form a body with a mass smaller than the critical mass, the relative number of escaping neutrons increases, and a chain reaction and explosion result.