Answer:
6 knots
Step-by-step explanation:
Let the speed be v knots
then time taken to cover 500 M = 500 / v hrs
fuel consumption /hr = 216 + 0.5v^3
let F be the fuel consumption for trip
= [500/v][216 + 0.5v^3]
= 500[216/v + 0.5v^2]
dF/dv = 500[ - 216/v^2 + v]
d^2F/d^2v = 500[432/v^3 + 1] , i.e. +ve
so setting dF/dv will give a minima
500[ -216/v^2 + v] = 0
or v = 216/v^2
or v^3 = 216
solving, we get v = [216]^(1/3) = 6 knots
3 to 9 clouds are smiley faces Explaintion- hope it’s right
Answer:
Option C. 
Step-by-step explanation:
we know that
Using a Excel tool (Correl function)
see the attached table
The r-value is 
A) y= -2, 3, 7
B) y= 8, 0, -6
C) y= -8, 1, 7
d) y= 1, -2, -6
(-4, 2), (-1, 2), and (-4, 0