PIease help me to find this answer

Find the ratios of the corresponding sides

Aley is at the store buying some supplies for an art project. she decides to buy some colored pencils for $3.95 and a drawing tablet. the total cost of the supplies before sales tax is $6.94. what is the cost of the drawing tablet? $10.89 $2.99 $1.76 $3.01

Which equation can be used to determine the reference angle, r, if 0=7 pi/12?