Power is the rate at which energy is consumed. When 1 J of energy is consumed in one second, the power consumed is 1 watt.
The microwave consumes 1.5 kJ of energy.
In joules, the energy consumed is 1500 J

Here, E is the energy consumed in time interval <em>t.</em>
The power rating of the microwave is therefore,

Thus, the power rating of the oven is 1500 W or 1.5 kW
The mass of the child in this problem is 24 Kg, the unit for mass is in Kilogram.
The mass will change only if it travels close to the speed of light.
Can a measurement be exact? No
Answer: c) Positive acceleration describes an increase in speed; negative acceleration describes a decrease in speed.
Hey
On Earth, you can move or you can not move. if you are moving 50 mph that means relative to Earth (not the Andromeda galaxy). When you start moving (accelerating) you are now moving relative to Earth. when you start slowing down (decelerating [most scientists just say you have negative acceleration]) you are starting to match your velocity to Earth's velocity.
Hope it helped and made any sence at all.
Spiky bob your answerer.