What type of lava is produced at a divergent plate boundary?

Which statement is true for light passing into a medium that is more optically dense than the first medium through which it past

According to social exchange theory, altruistic behaviors benefit the individual who performs them. t/f

For general projectile motion, when the projectile is at the highest point of its trajectory, its acceleration is zero? a)the horizontal and vertical components of its velocity are zero. b) its velocity is perpendicular to the acceleration. c)the horizontal component of its velocity is zero. d)its velocity and acceleration are both zero.