A ball is thrown vertically upwards with a speed of 10 m/s and vertically downwards with the same speed simultaneously. The time difference between them in reaching the ground )(in s) is:$\left(\mathrm{g}=10\mathrm{m}/{\mathrm{s}}^2\right)$

 

• A

  12

• B

  6

• C

  2

• D

  1