Physics question, ?

a cue ball with mass 170 g hits the stationary number 8 ball, which has mass 160 g. the cue ball and the 8 ball move with a speed of 0.2 m/s and 0.3 m/s respectively after the collision. what was the speed of the cue ball before the collision?

a) 0.2502 m/s
b) 0.4823 m/s
c) 0.5008 m/s
d) 0.5319 m/s

Which type of wave can travel without a medium

Which of the following are not typically included in the periodic table? a. atomic mass b. element symbol c. isotopes d. number of electrons

Question 11 of 13 (1 point) jump to question: a stairway, ladder, or ramp must be present in excavations in which of the following situations? a. all trenches must have access/egress b. the trench is more than 15 feet wide but only 1 ½ feet deep c. the trench is more than 4 feet deep and the devices must be within 25 feet of all workers