Each morning darnell does a combination of aerobics and stretching exercises. the exercises burn different amounts of calories per minute. the following system represents the time darnell exercises and the amount of calories burned. in the system, x represents the number of minutes darnell spends doing aerobics and y represents the number of minutes he spends stretching x+y=60
15x+5y=500

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