Evaluate each expression.

1) 3(6+7)
2) 5X3 X2
3) 729 + 7
4) 2 + 7 x 5
5) 9+8 -7
6) 9 - 32 4

A33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473. n = noekt no = initial mass (at time t = 0) n = mass at time t k = a positive constant that depends on the substance itself and on the units used to measure time t = time, in days