Q5. Hi please help with each question in photo. Will give thumbs up thanks!

Which of the following actions will increase the speed of sound in air? O decreasing the air temperature increasing the air temperature O increasing the frequency of the sound O increasing the amplitude of the sound wave O reducing the pressure of the air Suppose you're on a hot air balloon ride, carrying a buzzer that emits a sound of frequency f. If you accidentally drop the buzzer over the side while the balloon is rising at constant speed, what can you conclude about the sound you hear as the buzzer falls toward the ground? the frequency, decreases and the intensity increases the frequency remains the same, but the intensity decreases the frequency decreases and the intensity decreases the frequency and intensity increase As an airplane flying with constant velocity moves from a cold air mass into a warm air mass, how does the Mach number change? O decreases O remains the same O increases