Convert 0.0000505 nanometers into scientific notation

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Anika asks eva to roll a basketball and then a bowling ball to her. which requires more force to roll, and why?

A55-kg pilot flies a jet trainer in a half vertical loop of 1200-m radius so that the speed of the trainer decreases at a constant rate. knowing that the plane has a speed of 550 km/h at point a, and the pilot experiences weightlessness at point c (i.e., the normal force from the seat bottom is zero), determine (a) the deceleration of the plane, (b) the force exerted on her by the seat of the trainer when the trainer is at point b.