Which of the following equations represents a quadratic function ?

Cybil flips a coin and rolls a fair number cube at the same time. what is the probability that she will toss tails and roll a number less than 3?

While scuba diving, rajeev dove to a depth of 12.6 feet below the surface of the water and then descended another 8.7 feet. what expression can be used to find rajeev's new position? 12.6 – 8.7 –12.6 – 8.7 –12.6 – (–8.7) 12.6 – (–8.7)

What is the number 321,000,000 in scientific notation? also what is the number? ?