PLEASE HELP!! Part A: A keypad lock asks you to input a four-digit code. If you can choose any digit, 0 through 9, for each of the four digits, how many possible combinations are there?
Part B: Suppose the similar keypad lock asks for a four-digit code but does not allow you to repeat a digit. How many possible combinations are there for this lock?

When using the linear combination metho e linear combination method to solve a system of linear equations, the four options are:

With both problems. a. s.a. p directions on photo ^

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