Several dyes were mixed together and dissolved in water. You need to determine which dyes are in the solution, but not separate the entire mixture.
How can you separate out a small sample of the dyes for identification
purposes, but not separate the entire mixture?

Ahot-air balloon takes off from the ground traveling vertically with a constant upward acceleration of magnitude g/4. after time interval δt, a crew member releases a ballast sandbag from the basket attached to the balloon. how many seconds does it take the sandbag to reach the ground? (express your answer in terms of δt)