PLEASE HELP ONLY NINE DAYS LEFT I WILL GIVE BRANLIEST Jennifer and Mark make paper airplanes. They are conducting an experiment to see which airplane design will travel a longer distance. What do they need to do to properly conduct their experiment?

A. Apply the same force of motion when they release the airplanes.
B Apply different forces of motion when they release the airplanes.
CThrow one airplane into the wind and the other airplane against the wind.
D Use the force of the wind to decide which will travel farther.

Glass is transparent to visibile light under normal conditions; however, at extremely high intensities, glass will absorb most of the light incident upon it. this works through a process known as multiphoton absorption. in this process, several photons are absorbed at the same time. if very intense light whose photons carry 2ev of energy is shined onto a material with a band gap of 4ev, that light can be absorbed through two-photon absorption, because two photons have the right amount of energy to bridge the band gap. what is the minimum number of photons of 800-nm light that are needed to equal or exceed the band gap of fused silica glass

As part of your daily workout, you lie on your back and push with your feet against a platform attached to two stiff springs arranged side by side so that they are parallel to each other. when you push the platform, you compress the springs. you do an amount of work of 79.0 j when you compress the springs a distance of 0.230 m from their uncompressed length. (a) what magnitude of force must you apply to hold the platform in this position? (b)how much additional work must you do to move the platform a distance 0.230 m farther? (c) what maximum force must you apply to move the platform a distance 0.230 m farther?

What sort of waves exhibit the doppler effect?