Help pls ! Lead-196 has a half-life of 37 minutes. It decays into thallium-196. Suppose a sample contains 20 atoms of lead-196 and 60 atoms of thallium-196. About
how old is the sample?

Which one of the following research methods can show cause and effect

Ms. hidalgo opens the door to her classroom. her classroom is 60 degrees and the air outside is 80. predict what will happen using your knowledge of how heat flows.

The scalar triple product computes the magnitude m of the moment of a force vector f about a specified line. it is m = (r × f) · n, where r is the position vector from the line to the point of application of the force and n is a unit vector in the direction of the line. use matlab to compute the magnitude m for the case where f = [12, −5, 4] n, r = [−3, 5, 2] m, and n = [6, 5, −7].