Looks like the PMF is supposed to be

which is kinda weird, but it's not entirely clear what you meant...
Anyway, assuming the PMF above, for this to be a valid PMF, we need the probabilities of all events to sum to 1:

Next,





If

, then

, where we take the positive root because we know

can only take on positive values, namely 1, 2, and 5. Correspondingly, we know that

can take on the values

,

, and

. At these values of

, we would have the same probability as we did for the respective value of

. That is,

Part (5) is incomplete, so I'll stop here.
"how long..." is asking for time (t). "The amount of time spent in the air" is the time from when the ball was kicked (0 seconds) to the time it landed on the ground. Need to find the x-intercepts (one will be negative which will be invalid). You can do this by factoring ... <em>or by using the quadratic formula.</em> With the equation you provided, it is not factorable, so you must use the quadratic formula.
h = -16t² + 60t + 3
a=-16 b=60 c=3





or 
or 
t = -0.05 or t = 3.8 <em>disregard the negative</em>
Answer: 3.8 seconds
Answer:
B) 69°
Step-by-step explanation:
The missing measure is supplementary angle of 111° which means their sum is equal to 180°
180 - 111 = 69.
There are 12 inches in one foot. 120 x 12 = 1,440 inches. The correct ratio to be placed is the 5th one (aka 12 inches over 1 foot).