A meter scale is placed along the axis of a convex mirror of focal length 25cm, its nearer end being at a distance of 50cm. calculate size of the image formed. ans)

Phase changes are chemical changes. true or false

With i really need the correct answer!

The position of a crate sliding down a ramp is given by x=(0.05t^3) m, y=(1.7t^2) m, z=(6−0.85t^5/2) m, where t is in seconds. (a) determine the magnitude of the crate's velocity when t = 2 s. (b) determine the magnitude of the crate's acceleration when t = 2 s.