Prove sin^2 theta-sin^2 theta is sin tetha sin 3 theta
how to prove..pls

Haruka hiked several kilometers in the morning. she hiked only 66 kilometers in the afternoon, which was 25% less than she had hiked in the morning. how many kilometers did haruka hike in all?

Cone a has a surface area of 384 ft2 and cone b has a surface area of 96 ft? . what is the ratio of their volume?

Eric drove 275 miles in 5 hours. at the same rate how long would it take him to drive 495 miles?