In the investing sense, securities are broadly defined as financial instruments that hold value and can be traded between parties. In other words, it's a catch-all term for stocks, bonds, mutual funds, exchange-traded funds or other types of investments you can buy or sell.
 
        
             
        
        
        
Answer: a) 4.15m/s
b) 11.22m/s
c) 14.76m/s
Explanation: d). 
Sometimes it is possible to neglect an external impulse if it is not in the direction of interest. 
Also, a small force acting over a long time can easily provide more impulse
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