What should you do before you begin to plan a
scientific investigation?

The sunlight shines uv radiation on earth,a microwave oven radiates waves on food

I'm having some difficulty seeing the diagram clearly.but the question says there's a net inward force on the object.so we know right away,  from newton's 2nd law of motion, thatthat baby is accelerating.  it doesn't even matter which way thenet force is pointing.  if there's any net force, then either theobject's speed or else its direction must be changing.

Idon't get it? what do you mean by playing 17 hours on the wii