The best and most correct answer among the choices provided by your question is the first choice or letter A.
<span>The minimum amount of energy that has to be added to start a reaction is the activation energy.</span>
I hope my answer has come to your help. Thank you for posting your question here in Brainly. We hope to answer more of your questions and inquiries soon. Have a nice day ahead!
Bike
because it involves lots of angular mechanics that allow it to balance itself when moving.
all other examples have a constant force being applied into the system which is very easy to formulate, therefore they are simple machines.