20 points and giving out brainliest answers fast

which voice can produce a pitch that has a speed of 343 m/s and a wavelength of 0.68 m? check all that
a. bass
b. baritone
c. tenor
d. contralto
e. soprano

Abar magnet cut in half will form a total ofpoles.a)fourb)eightc)two

Anonzero net force acts on a particle and does work. which one of the following statements is true? the kinetic energy of the particle changes, but the speed of the particle does not change. the kinetic energy of the particle does not change, but the speed of the particle does change. the kinetic energy of the particle changes, but the velocity of the particle does not change. the kinetic energy and the speed of the particle change, but the velocity of the particle does not change. the kinetic energy, speed, and velocity of the particle change.

Which body is in equilibrium? (1) a satellite orbiting earth in a circular orbit (2) a ball falling freely toward the surface of earth (3) a car moving with a constant speed along a straight, level road (4) a projectile at the highest point in its trajectory