Need asap!

which most likely a solid at room temperature?
a chlorine
b hydrogen
c neon
d potassium

a police car is parked by the side of a highway and its siren emits sound measuring 750 hz. as you approach the police car from a distance, you hear a change in the sound. the change is the sound's?
a frequency
b pitch and frequency
c frequency and wavelength
d pitch, intensity, and loudness

describe the location of non metals on the periodic table?
a middle
b upper left corner
c lower left corner
d upper right corner

displacement is to velocity as is to acceleration.
a direction
b speed
c time
d velocity