Afair coin is tossed 3 times in a row. what is the probability that heads appears exactly 2 times?

Which of the following answers is 7/9 simplified? 7/9 2/9 11/9 2/7

20 ! brainliest ! add and simplify your answer.

Apossible wavelength for the color blue is 0.000000492 meter. which of the following is a reasonable estimate for this wavelength for the color blue? a. 5 × 10-6 m b. 5 × 107 m c. 5 × 10-7 m d. 5 × 106 m