8 less than y algebraic expression

Which of the following pair(s) of circles have las a common external tangent? select all that apply. a and b a and c b and c

Ahypothesis is: a the average squared deviations about the mean of a distribution of values b) an empirically testable statement that is an unproven supposition developed in order to explain phenomena a statement that asserts the status quo; that is, any change from what has been c) thought to be true is due to random sampling order da statement that is the opposite of the null hypothesis e) the error made by rejecting the null hypothesis when it is true

The difference of three and the reciprocal of a number is equal to the quotient of 20 and the number. find the number.