Answer:
A
Step-by-step explanation:
how long is the ball in the air ?
that is the same as asking : after how many seconds will the ball hit the ground (= reach the height of 0) ?
so, that means we need to find the zero solution of h(t).
at what t is h(t) = 0 ?
when at least one of the factors is 0 :
2(-2 - 4t)(2t - 5)
we have 3 factors
2 : can never be 0.
(-2 -4t) : can only be 0 for negative t, which does not make sense in our scenario (we cannot go back in time, only forward).
(2t - 5) : is 0 when 2t = 5 or t = 2.5
so, A is the right answer.
FYI : the starting height (on the hill) is given by t = 0 :
2(-2 - 0)(0 - 5) = 2×-2×-5 = 20 ft
.0075 is simplest... or .0075/1 if it needs to be a fraction i guess
Answer:
(-3.07, 11.07)
Step-by-step explanation:
Given that a sports writer wished to see if a football filled with helium travels farther, on average, than a football filled with air. To test this, the writer used eighteen adult male volunteers. These volunteers were randomly divided into two groups of nine subjects each.
Group Group One Group Two
Mean 300.00 296.00
SD 8.00 6.00
SEM 2.67 2.00
N 9 9
The mean of Group One minus Group Two equals 4.00
standard error of difference = 3.333
df = 16
t = 1.2000
Margin of error = 3.3333* t critical = 3.3333*2.121
95% confidence interval of this difference: From -3.07 to 11.07
Answer:
It is 80
Step-by-step explanation:
Percentage Calculator: 240 is what percent of 300? = 80.
