I really with these questions

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The discussion revolves around two physics problems involving kinematics and relative motion. For the first question, the height of the tower can be determined by applying kinematic equations for both balls thrown in opposite directions, ensuring to clarify that they are thrown with the same speed. The second question involves calculating the speed of the river based on the boat's speed and the time taken to cross the river. Participants emphasize the importance of correctly interpreting the problem statements and using appropriate formulas to arrive at the solutions. Clear understanding and application of physics principles are essential for solving these problems effectively.
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I really need help with these questions...!

Question 1.
Two balls A and b are thrown with same velocity u from the top of a tower.Ball A is thrown vertically upwards and B is thrown vertically downwards.
If time of A=6s and B=2s..Find height of tower.

Question 2.
A boat having speed of 5km/hr in still water, crosses a river of width 1km along the shortest possible path in 15 minutes.Find the speed of the river in km/hr.


I've tried everything but the answers are just not coming out right..
pl help...
 
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I'll give you some hints that should be useful - then you should try working the problems.First, you need to be careful when writing out the questions. In question one you say that both balls are thrown with the "same velocity" but then contradict yourself and say that one is thrown upwards and the other downwards - you should say they are thrown with the same speed.1. You will need to use one the basic kinematics formulas to solve this question. You will have two equations - one for ball A and one for ball B and you should be able to use these to solve for the height of the tower. (Hint: You may need to use substitution or elimination.)2. If you were to row a boat across a river in stationary water what would the shortest possible distance be?
 

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