CAN SOMEONE PLEASE HELP ME EXPLAIN THIS THIS IS DUE TOMORROW AND I STILL HAVEN'T TURNED IT IN. I NEED TO EXPLAIN IT,

Lilianna uses 3/4 calories per minute just by sitting. she uses 1 more calorie per minute by walking. lilianna uses a total of 12 1/4 calories walking to the park. lilianna uses the equation, d(.75+1)=12.25 to represent the situation. what does the variable d represent in the equation?

List the elements of the set in roster notation. (enter empty or ∅ for the empty set.) {x | x is a letter in the word hippopotamus}

Need on this one asap im almost done with this subject