Biology as Unit 1 Cardiac output and stroke volume question thats really HARD ! :)

hi there, i was stuck on this question, could anybody help answer it and just show a method of how to do it because im so confused lol :) THANKSSS :)

heres a link to the question that includes a table and then 2 questions , sorry its a bit bad quality but it was the quickest way i could think of to upload it :)

http://s19.postimage.org/4nva03opf/QUESTION_PART_1.png
http://s19.postimage.org/o89t2vpar/QUESTION_PART_2.png

This was a tough questions. But here is how i solved it.

A) First you have to figure out what is your STROKE VOLUME (SV)?
- SV = End Diastolic Volume - End Systolic Volume

-- End Diastolic Volume means: The amount of blood in the ventricle after its filled up all the way at the END of diastole and BEFORE any blood is pumped out from the ventricle. which would be the HIGHEST number " 148 cm3".

-- End Systolic Volume means: The amount of blood that is (REMAINING) in the ventricle AFTER the ventricle has pumped out some amount of blood during systole. which would be the SMALLEST number "55 cm3"

SV = (148 cm3) - (55 cm3) ----> SV = 93 cm3

B) Heart Rate: Question states that the figure provided is for ONE cardiac cycle which is the same thing saying "One Heart Rate". but since it is in "Seconds" you have to convert it to "Minute".

HR= ( X / 0.7sec ) x ( 60sec / 1min) = 60/0.7 ----> HR= 86 beats/Min


C) Now just plugin the numbers in your Cardiac Output formula and thats it.

CO = SV x HR -----> CO = (93 cm3) x ( 86 beats/min) ------> CO= 7998 cm3/min



I hope this is correct :)