Two automobiles traveling at right angles to each other collide ...

[burchfield96]

Two automobiles traveling at right angles to each other collide and stick together. Car A has a mass of 1200 kg and had a speed of 25 m/s before the collision.
 
  Car B has a mass of 1600 kg. The skid marks show that, immediately after the collision, the wreckage was moving in a direction making an angle of 40 with the original direction of car A. What was the speed of car B before the collision?
  A)
 
  16 m/s
 
  B)
 
  18 m/s
 
  C)
 
  11 m/s
 
  D)
 
  21 m/s
 
  E)
 
  14 m/s

Question 2

How many different kinds of leptons are known to exist, including antiparticles as different kinds?
 
  A) 12 B) 4 C) 2 D) 8 E) 6

[Toya9913]

Answer to Question 1

A

Answer to Question 2

A

[burchfield96]

Thank you!

[Toya9913]

Always glad to help...