Bats, which have a high-calorie diet of insects and face little danger from predators, sleep a lot. In contrast, cows, which have a low-calorie diet and are at risk from predators, sleep loss. What function of sleep theory do these differences support?
a. Sleep enhances immune function.
b. Sleep repairs and restores.
Oc Sleep conserves and protects.
Od. Sleep enhances learning and memory.
yers

What are similarities and differences between refraction, reflection, diffraction and absorption?

The ultracentrifuge is an important tool for separating and analyzing proteins. because of the enormous centripetal accelerations, the centrifuge must be carefully balanced, with each sample matched by a sample of identical mass on the opposite side. any difference in the masses of opposing samples creates a net force on the shaft of the rotor, potentially leading to a catastrophic failure of the apparatus. suppose a scientist makes a slight error in sample preparation and one sample has a mass 10 mg larger than the opposing sample. if the samples are 12 cm from the axis of the rotor and the ultracentrifuge spins at 70,000 rpm, what is the magnitude of the net force on the rotor due to the unbalanced samples? ( be thorough on your answer)

Why does gravity have a lesser than grater effect on higher altitudes?