What is the circumference of this circle

In the geometric progression –3, 12, −48… what term is 3,072?

The? half-life of a radioactive substance is 20 years. if you start with some amount of this? substance, what fraction will remain in 120 ? years

Choose the equation below that represents the line that passes through the point (2, 4) and has a slope of 3. a) y − 4 = 3(x − 2) b) y − 2 = 3(x − 4) c) y + 4 = 3(x + 2) d) y + 2 = 3(x + 4)