Answer:

Step-by-step explanation:
The path covered by the volleyball will be a downward parabola with the vertex being the highest point of the ball.
A general form of a downward parabola is given as:

Where  is the vertex of the parabola and 'a' is a constant.
 is the vertex of the parabola and 'a' is a constant.
Now, let 'h' be the vertical height and 't' be the time taken.
So, the equation would be of the form:

Now, as per question:
h = 2 seconds, k = 13 feet.

Now, taking a = 1. So, the formula that can be used is:

  
        
             
        
        
        
B. 24x2 is the correct answer
        
             
        
        
        
Here is the set up:
(1/4)/2 = (9/4)/y
Solve for y.
        
             
        
        
        
Answer: 4/13
Step-by-step explanation:
Number of cards in a deck = 52
Number of spades = 13
Number of aces = 4
Number of ace of spade = 1 
Probability of either a spade or an ace :
P(spade or ace) = P(spade U ace)
P(spade U ace) = p(spade) + p(ace) - p(spade n ace) 
Probability = required outcome / Total possible outcomes
P(spade) = 13 / 52
P(ace) = 4 / 52
P(spade n ace) = 1 / 52
P(spade U ace) = p(spade) + p(ace) - p(spade n ace) 
= 13/52 + 4/52 - 1/52
= 16 / 52 = 4 /13