Answer:
b. How many people saw the ad
d. How many people sign up for lessons after seeing the ad
Explanation:
Conversion tracking is a free resource that indicates what occurs once a customer has interacted with your ads (if he/she bought one of your items, subscribed to your newsletter, got in touch with your business, or installed your app in his phone). After a customer has fulfilled an action you point as valuable, this action becomes known as conversion.