What is the significance of the discovery of exoplanets? need asap
a.
they may possibly be inhabited or harbor life.
b.
they can provide natural resources for the future.
c.
they our understanding of the formation of planetary bodies.
d.
they calibrate gps satellites.
e.
they understand the nature of the expansion of the universe.

An inclined plane wrapped around a metal shaft is a a. lever b. screw c. pulley d. wedge

The focal length of a relaxed human eye is approximately 1.7 cm. when we focus our eyes on a close up object, we can change the refractive power of the eye by about 16 diopters. (a) does the refractive power of our eyes increase or decrease by 16 diopters when we focus closely? explain. (b) calculate the focal length of the eye when we focus closely.

If steel is more dense that lake water, why can a boat float