1.If some unimaginable calamity destroyed the Sun, using the astronomical unit for the Earth-Sun distance and the value for the speed of light above, how long would we still have light after the Sun ceased to exist? (5)

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.

How many neutrons does element x if it’s atomic number is 28 and its mass number is 87

Describe how the motion of a spring being pushed forward and backward is similar to the motion of air particles in a sound wave.