Aduck is floating on water waves that have frequency if 0.25 hz how long would it take the duck to have 5 cycles

When you drop a pebble from height a it reaches the ground with speed v if there is no air resistance. from what height should you drop it so it will reach the ground with three times the speed? (a) 9m (b) 3m (c) 6m (d) 18m

The metric unit of electrical power is the watt volt ampere ohm

The energy equivalent of the rest mass of an electron is