Answer:
The velocity is 

Henrietta is at distance 
 from the under the window 
Step-by-step explanation:
From the question we are told that 
 The speed of Henrietta is 

 The height of the window from the ground is 

 
Generally the time taken for the lunch to reach the ground assuming it fell directly under the window is 
 

=> 
 
=> 
 
Generally the time taken for the lunch to reach Henrietta is mathematically represented as 
 

Here 
 is the time duration that elapsed after Henrietta has passed below the window the value is given as 4 s
 Now 
 
 
=> 
 
Generally the distance covered by Henrietta before catching her lunch is 
 

=> 

=> 

Generally the speed with which Bruce threw her lunch is mathematically represented as 
 

 
