Answer:
45.27feet
Step-by-step explanation:
Given the height of the balloon (in feet) represented by the equation h=−16t2+28.7t+32.4, where t is the time (in seconds)
Note that the velocity of the balloon at maximum height is zero, hence;
v = dh/dt =0
-32t+28.7 = 0
-32t = -28.7
t = 28.7/32
t = 0.897secs
Get the maximum height
Recall that h=−16t²+28.7t+32.4
h = -16(0.897)²+28.7(0.897)+32.4
h= -12.87+25.74+32.4
h = 45.27feet
Hence the maximum height reached is 45.27feet
B. 54
Because 54+13=67
67+54=121
Answer:
(B) The correct interpretation of this interval is that 90% of the students in the population should have their scores improve by between 72.3 and 91.4 points.
Step-by-step explanation:
Confidence interval is the range the true values fall in under a given <em>confidence level</em>.
Confidence level states the probability that a random chosen sample performs the surveyed characteristic in the range of confidence interval. Thus,
90% confidence interval means that there is 90% probability that the statistic (in this case SAT score improvement) of a member of the population falls in the confidence interval.
Lets take (-4) - (-6)
= -4 + 6 (here we changed the sign because in integers when you are subtracting <span>an integer, we put its opposite..thats the rule .)
=. -4 + 6 = 2
so here we got the answer as 2 .....this shows that </span>your answer will be less than the integer you started with ....this is because here in subtraction we will first change the sign and then follow the same rules of addition ...so here if both the numbers have opposite signs then we subtract and put the greater number sign .....
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Hope i am right !!!</span>
