Most metallic elements, such as copper and iron, have high melting points. This
is a useful property because

F. it keeps cars made of metal from
becoming hot on summer days

G. it enables people to use pots and pans
made of metal to cook food

H. it prevents machine parts made of
metal from rusting

J. it makes metals easier to melt so they
can be poured into molds to make
precision tools

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.