What does law of conservation of mass mean? ?

Large electric fields in cell membranes cause ions to move through the cell wall. the field strength in a typical membrane is 1.0 x 10 7 n/c. what is the magnitude of the force on a calcium ion with charge +e? what is its acceleration? is it possible for a particle with the same charge as as calcium to have a different acceleration if placed at this location? what would change the acceleration: mass of the particle? diameter of the particle?

Aspaceship starting from a resting position accelerates at a constant rate of 9.8 meters per second per second. how far will the spaceship travel if its final speed is 1 percent the speed of light (300,000,000 m/s)? a. 3.1 × 106 m b. 2.94 × 108 m c. 7.8 × 1010 m d. 4.6 × 1013 m

Consider a production line with five stations. station 1 can produce a unit in 9 minutes. station 2 can produce a unit in 10 minutes. station 3 has two identical machines, each of which can process a unit in 12 minutes (each unit only needs to be processed on one of the two machines. station 4 can produce a unit in 5 minutes. station 5 can produce a unit in 8 minutes. which station is the bottleneck station?