Waves with shorter wavelengths have more energy.  Dean is trying to get a wavelength that has less energy, so Dean will have his wavelength produce waves that are shorter or longer?
longer

The rocket goes upwards because the hot gases shoot downwards out of the nozzle. The faster the gases go downwards, the faster the rocket goes upwards.  Boris was tasked with developing a hypersonic rocket. He built two prototypes that were identical except that they have different gas velocities out of the nozzle. Which rocket was likely the fastest the rocket with highest gas velocity or the rocket with lowest gas velocity?
the rocket with highest gas velocity

We also saw that adding resistors to a series circuit increases the total resistance of the circuit, causing the current to decrease.  If Mona is building a new circuit and she adds more serial resistors to it, what happens to the total current in that circuit increases or decreases?

decreases