How to solve equations with variables on both sides step by step?

Luisa sells stuffed animals. she sells her stuffed elephant for $34.90, and the sales tax is 6% of the sale price. about how much is the sales tax on the elephant?

Marion has a bicycle that she is planning to take for a ride. the rim of the rear wheel lies 41 cm from the center of the wheel. the tire itself has a thickness of 3 cm. in order for marion to ride her bicycle 96,712 cm approximately how many rotations will the rear wheel make?

∠a and ∠ b are complementary. if m∠ b = 80°, what is the measure of ∠ a? 10° 80° 90° 100°