Why is most space exploration accomplished with spacecraft that do not have astronauts on board

Which factors are used to calculate the kinetic energy of an object?

What effect does an u balanced force have on an object?

How does an atom of bromine-79 become a bromide ion with a - 1 charge?

Water on Earth was (a) transported here by comets; (b) accreted from the solar nebula; (c) produced by volcanoes in the form of steam; (d) created by chemical reactions involving hydrogen and oxygen shortly after Earth formed.

You can filter the particles out of a suspensions. b colloids. c solutions. d all of the above

What is the frequency of a wave with a velocity of 21.2 m/s and a wavelength of 8.3m?

Positive ions have blank protons than electrons

What is the weight, in n, of an object with a mass of 200 kg at a location where g = 9.6 m/s2. round the final answer to the nearest whole number?

A 1.7 kg book is lying on a 0.77 m - high table. You pick it up and place it on a bookshelf 2.0 m above the floor. how much work does gravity do on the book?

What is the difference between diffusion and osmosis?