How should you use a heart rate monitor?

a. measure your heart rate before, during, and after workouts

b. measure your heart rate once a week before workouts

c. measure your heart rate after every other workout session

d. measure your heart rate the day after an intense workout

for me i have felt invisible when i was clearly struggling,or,i made a great achievement ,and,nobody took to notice me either because they just didn't see it,or,people just turned their back on me.i can see a person being invisible by choice,or,without choice like i did.the people who are invisible by choice don't try to talk to people,don't try to make friends,and,keep to themselves.i haven't been one of those people so i couldn't give you a reason.

hope this and can i get bainliest my dude : d