The statement ‘Big bang theorists
believe that the universe is expanding and will eventually contract’ is false. The
answer is letter B. The big bang theory suggests that the origin of the
universe began with that exploded and expanded. It also states that the
universe began in a single form of high condensed reactive matter and exploded
forming the galaxies, planets, stars and other celestial bodies.
For example science has discovered many amazing things like atoms,molecules which led to the development of nuclear reactors etc. Challenges would be like trying to prove theories like evolution for 100 of years trying to discover all the stuff we still don’t know exists all the mysteries of life. A lot of science is still theory we can’t prove some things until we have more advanced technology etc.
Answer:
metal> metalloids >nonmetals (Electrical conductivity)
Explanation:
Electrical conductivity of objects can be compared by the bonding energy of electrons in them.
Metals have less bonding energy of electrons, so even at room temperature their are significant number of free electrons to carry electrical current.
Nonmetals have a very high bonding energy of electrons, so at room temperature negligible number of free electrons are present so electrical conductivity is very low.
Metalloids have both metallic and non metallic features. The electron bonding energy falls in between that of metals and nonmetals. So electrical conductivity also lies in between metals and nonmetals.
<span>Strong nuclear forces hold the nucleus of an atom together. Weak nuclear forces are involved when certain types of atoms break down.</span>
