Which of these has components that can have a varying ratio? a. element b. compound c. mixture d. ion

Two loudspeakers, 5.5 m apart and facing each other, play identical sounds of the same frequency. you stand halfway between them, where there is a maximum of sound intensity. moving from this point toward one of the speakers, you encounter a minimum of sound intensity when you have moved 0.33 m . assume the speed of sound is 340 m/s.part a) what is the frequency of the sound? part b) if the frequency is then increased while you remain 0.21 m from the center, what is the first frequency for which that location will be a maximum of sound intensity? express your answer to two significant figures and include the appropriate units.

The friction of the water on a boat produces an acceleration of -10. m/s2. if the boat is traveling at 30. m/s and the motor is shut off, how long it take the boat to slow down to 5.0 m/s?

The flame produced by the burner of a gas (propane) grill is a pale blue color when enough air mixes with the propane (c3h8) to burn it completely. for every gram of propane that flows through the burner, what volume of air is needed to burn it completely? assume that the temperature of the burner is 195.0°c, the pressure is 1.05 atm, and the mole fraction of o2 in air is 0.210.