What two instruments made navigation much easier in the 1900s?

global positioning satellite (gps) and two-way radio
the chronometer and the astrolab
the cross-staff and the compass.
the chronometer and the compass.

Adoctor is trying to diagnose a patient with dry skin. which of the following resources would be the most ? a magazine ad about soft skin a growth chart online articles about dry skin medical books

Which would best keep the oxygen cycle stable? a. cutting down jungles to create farmland b. eliminating parks in large cities c. dumping toxic chemicals into the ocean d. reducing the amount of deforestation d. reducing the amount of deforestation

Which spheres are involved when sedimentary rocks formed from parts of seashells at the bottom of the ocean? a.) biosphere, atmosphere, geosphereb.) geosphere, hydrosphere, biosphere c.) geosphere, exosphere, hydrosphered.) hydrosphere, biosphere, atmosphere