If the arrow is in the air, then when it hits the ground, h(t)=0. So:
0=-16t²+63t+4
16t²-63t-4=0
(16t+1)(t-4)=0
t= -1/16 or 4
Using the positive result of 4, we get t=4 seconds as the time the arrow was in the air
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This is simple conversion.
Start from getting the numbers of hours.
12 weeks × 5 days × 45 minutes will get the number of minutes spent total (2700mins). Divide this by 60 min to get the number of hours spent total - 45 Hours.
to get the rate - r=laps/time
1800laps/45 hours
rate = 40laps/hour
I the average score is 750 and standard deviation ( sigma ) is 50 points, then score 700 - 800 is between (750 - 1 sigma) and (750 + 1 sigma).
That is 34.1 % + 34.1 % = 68.2 % of the whole population.
2,000 · 0.682 = 1.364
We expect 1,364 students to score between 700 and 800 points.
Answer:
615.75216
Step-by-step explanation:
A=πr2
=π·14^2
≈615.75216
