A wave has a wavelength of 15 mm and a frequency of 4.0 hertz. What is its speed?

Which seasons are the northern and southern hemispheres experiencing in the image? it is summer in both the northern and southern hemispheres. it is summer in the northern hemisphere and winter in the southern hemisphere. it is winter in both the northern and southern hemispheres. it is winter in the northern hemisphere and summer in the southern hemisphere.

After the near spacecraft passed mathilde, on several occasions rocket propellant was expelled to adjust the spacecraft's momentum in order to follow a path that would approach the asteroid eros, the final destination for the mission. after getting close to eros, further small adjustments made the momentum just right to give a circular orbit of radius 45 km (45 × 10^3 m) around the asteroid. so much propellant had been used that the final mass of the spacecraft while in circular orbit around eros was only 545 kg. the spacecraft took 1.04 days to make one complete circular orbit around eros. calculate what the mass of eros must be.

As a pendulum bob swings back and forth several times, the maximum height it reaches becomes less and less. this is because more and more of the pendulum bob's energy is being transformed into a. heat energy b. kinetic energy c. potential energy d. kinetic energy and potential energy