My cupcake recipe makes $12$ cupcakes and requires $1\frac12$ sticks of butter. i can only buy whole sticks of butter. how many whole sticks of butter must i buy to make $100$ cupcakes?

Find the sum to the equation 3+6+9+

Kayla wants to find the width, ab, of a river. she walks along the edge of the river 65 ft and marks point c. then she walks 25 ft further and marks point d. she turns 90° and walks until her location, point a, and point c are collinear. she marks point e at this location, as shown. (a) can kayla conclude that δ and δ are similar? why or why not? (b) suppose de = 15 ft. what can kayla conclude about the width of the river?

Can someone me with #s 8, 9, and 11. with just one of the three also works. prove using only trig identities.