c is the answer i hope this help
which one do you need help with?
Answer:
15
Step-by-step explanation:
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
Answer:
28 years
Step-by-step explanation:
Sum of the years of Lance , Ted, Rosalinda = 39 + 22 +45 = 106 year
Sum of the years of Lance , Ted, Rosalinda & Erik = 33.5*4 = 134.0 year
Age of Erik = 134 - 106 = 28 years