What happens next in this paragraph?

How to know what is normal for a horse
Check the heart rate.
This can be checked by placing the hand under the left elbow. Count the beats for 10 seconds then multiply the beats by 6.
Select from:
(a). That will tell you the heart rate per minute. A normal heart rate is 35-40 beats per minute.
(b). These will be the kind of beats that tell you how the horse is feeling. The song helps to locate this kind of interval.
(c). If the heart rate is within 55%, the horse is calm. If it is below 55%, the horse is agitated.
(d). As you count up, the heart rate will drop. The heartbeat will be somewhere around 6 beats per minute (bpm).
(a).