closed and unsecure circuit
For speed you can differentiate the equation, for acceleration you can again differentiate the equation .
at t=0 the particle is slowing down , when you get equation for velocity put t=0 then only -1 is left
The best option is C. This is due to friction.
One cubic centimeter and one milliliter are equal volumes.
If the Earth didn't tilt then we wouldn't have seasons.