To do his work that he didn't want to do.
 
        
             
        
        
        
Answer:
The Principle of Zero Products states that if the product of two numbers is 0, then at least one of the factors is 0. (This is not really new.) If ab = 0, then either a = 0 or b = 0, or both a and b are 0.
hope it helped 
 
        
                    
             
        
        
        
The probability that the train will be there when Alex arrives is 5/18
If Alex arrives at any time after 1.20pm the chances that train will  be there is 1/3.
However  if alex arrives at 1.00pm exactly there is no chance the train will be arrive there.
The probability that the train will be there increase linearly to 1/3 as alex's arrival time moves from 1.00pm to 1.20pm.
By arranging the probabilities over the first 20 minutes to get a 1/6 chance the train will be there if alex arrives between 1.00pm to 1.20pm 
we get the final answer by 
=1/3( 1/6 + 1/3 + 1/3)
=5/18
So, the probability that the train will be there when Alex arrives is 5/18
Learn more about PROBABILITY here 
brainly.com/question/24756209
#SPJ4
 
        
             
        
        
        
Answer:
Step-by-step explanation:

 
        
                    
             
        
        
        
Answer:
<h2>780</h2>
Step-by-step explanation:
What is the sum of the series 5^n from n=1 to 4.
5^1 + 5^2 + 5^3+ 5^4 =
5 + 25 + 125 + 625 =780