Can you please answer and explain this assignment?

Let's see what happens if we change the speed of sound againl Sulphur hexaflouride is a gas that is much more dense than atmosphereic air (which is mostly nitrogren and oxygen). What would happen to the resonant frequencies of the vocal tract if our three people above were to breathe in sulphur hexafluoride? (like from a balloon!) The new value for C is 135 m/s a. Consider a woman with a 14cm vocal tract use the following equation to identify the formants of her neutral vowel i. F1 = ii. F2 = iii. F3 = b. Consider a man with a 17cm vocal tract use the following equation to identify the formants of his neutral vowel i. FA= ii. F2 = iii. F3 = c. Consider a child with a 11cm vocal tract use the following equation to identify the formants of her neutral vowel i. F1 = ii. F2 = iii. F3 = 4. Why does changing the speed of sound change the resonant frequencies of the vocal tract? (think ALL the way back to Basic Acoustics and consider how the speed of sound changes wavelength)