77. The mass of a radioactive sample is given by M(t)=M(0) 10-4, where t is the time in years, M, is the initial mass, and k is a constant. If 400 grams of
this material decays to 40 grams in 10 years, what is the value of k?

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