Answer:
when an x-ray passes trough matter, it undergoes a process called attenuation
Answer:
A system of two co-axial cylindersof different diameters which rotate together is called wheel and axle example; the door knob , knob of the tap ,screw driver,water tap
Some fruits and vegetables sink in water and some float in water. None swim.
Answer:
atmosphere
Explanation:
majority of nitrogen found in atmosphere,it's about 78% and present in form of gas
