Answer:
A≈87.96
Step-by-step explanation:
A=2πrh+2πr2
= 2pi(2)(5) + 2pi(2)2
Answer:
2 hours for the 2 pipes
Step-by-step explanation:
1 pipe for a tank is 4 hours, but since 2 pipes is 2 hours less, it would take the two pipes together 2 hours
Answer:

Step-by-step explanation:
General equation of a parabola that opens up is
, a>0
So equation becomes
which implies option A and option B can never be true for this parabola.
Also this parabola's vertex lies in 3rd quadrant where coordinates of both x and y will be negative.
So, the equation of parabola will be of the form 
Hence, option 4 that is
is correct.
D1,..,d9 = 0,0,2,2,2,3,4,6,8 //there are 9 values, in ascending order
Q2 (median) = d5 = 2 //value in the middle
Q1 = (d2+d3) / 2 = (0+2)/2 = 1
(Q1 is middle value of d1,d2,d3,d4, but there is no middle element among four elements, that is why arithmetic mean is taken)
Q3 = (d7+d8) / 2 = (4+6)/2 = 5
interquantlie range = IQR = Q3 - Q1 = 5 -1 = 4
answer: 4
Answer: a) 84 and b ) 2084
Step-by-step explanation:
Given : Sample standard deviation : s= $22.82
(Population standard deviation is unknown ) , so we use t-test.
Critical value or the 95% confidence intervals :
Formula to find the sample size :

a) E = 5


i.e. Required sample size : n= 84
b) E = 1


i.e. Required sample size : n= 2084