What system of units do scientist use to measure the properties of matter

If angle "a" is 25°, angle "b" is: a) equal to angle c b) less than angle c c) greater than angle c

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

If you held a stone over the mouth of a well and then let it go , what would happen to the stone? explain your answer.