Which of the following is ALWAYS a property of a parallelogram A. 4 congruent sides

B. opposite sides are parallel

C. 4 angles that measure 90 degrees

D. 4 equal angles

The boiling point of water at an elevation of 0 feet is 212 degrees fahrenheit (°f). for every 1,000 feet of increase in elevation, the boiling point of water decreases by about 2°f. which of the following represents this relationship if b is the boiling point of water at an elevation of e thousand feet? a) e = 2b - 212 b) b = 2e - 212 c) e = -2b + 212 d) b = -2e + 212

Solve this riddle: i am an odd number. i an less than 100. the some of my digit is 12. i am a multiple of 15. what number am i?

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