[" 7) A solid sphere falls with a terminal velocity of "20ms^(-1)" in air.If it is allowed to fall in "],[" vacuum,"],[" A) terminal velocity will be "20ms^(-1)],[" + B) terminal velocity will be less than "20ms^(-1)],[" C) terminal velocity will be greater than "20ms^(-1)],[" D) no terminal velocity will be attained "]