By Stokes' theorem,

where
is any oriented surface with boundary
. We have


Take
to be the ellipse that lies in the plane
with boundary on the cylinder
. Parameterize
by

with
and
. Take the normal vector to
to be

Then we have



The answer for apex users are:
All of the radii of a circle are congruent
CPCTC
SSS triangle congruence postulate
Answer:
A. 9 sqrt 2
Explanation:
Plug in hypotenuse and given side into
a^2 + b^2 = c^2 and solve.
Answer:
- boat: 16 mph
- current: 4 mph
Step-by-step explanation:
speed = distance / time
The rate downriver is (60 mi)/(3 h) = 20 mi/h.
The rate upriver is (60 mi)/(5 h) = 12 mi/h.
The rate of the boat in still water is the average of these:
(20 +12)/2 mi/h = 16 mi/h
The rate of the current is the difference between the boat speed and actual speed:
16 mi/h - 12 mi/h = 4 mi/h