A circular cylinder, open at one end, has radius r cm and external surface area 27\pi cm^{3}. (i) Show that the volume of the cylinder, V cm^{3}, is given by V=\frac{\pi}{2}(27r-r^{3}).
(ii) Given that r can vary, find the stationary value of V and determine whether this value is a maximum or a minimum.

start with a line segment pq that we will copy. mark a point r that will be one endpoint of the new line segment. set the compasses' point on the point p of the line segment to be copied. adjust the compasses' width to the point q. the compasses' width is now equal to the length of the line segment pq.

step-by-step explanation:

b. 1.25 hr

step-by-step explanation:

if you have a constant speed of 60 mph, then you have a ratio between 60 mi. to 1 hr. dividing both sides by 60 we get the ratio

1 mi. to

then mult. both sides by 75 we get the ratio

75 mi. to

simplifying we get

75 mi. to

or 1.25 hr.

answer: i wpould go with c

step-by-step explanation: