1.  ekt = ?, where k = 0.0189 yr-1, and t = 25 yr. [Ans. 1.6]
2.  ab/c = ?, where a = 483 J, b = 73.67 J, and c = 15.67 [Ans. 2.27X103 J2 ]
3.  x + y + z = ?, where x = 48.1, y = 77, and z = 65.789 [Ans. 191]
4.  m - n - p = ?, where m = 25.6, n = 21.1, and p = 2.43 [Ans. 2.1]