The half-life of argon-44 is 12 minutes. Suppose you start with 20 atoms of argon-44 and wait 12 minutes. how many atoms of argon-44 will be left?

5 atoms
20 atoms
40 atoms
10 atoms

Where is the potential energy throughout the loading, cocking, and releasing of the trebuchet?

The temperature in gavin's oven is a sinusoidal function of time. gavin sets his oven so that it has a maximum temperature of 280°f and a minimum temperature of 240°. once the temperature hits 280°, it takes 20 minutes before it is 280° again. gavin's cake needs to be in the oven for 30 minutes at temperatures at or above 270°. he puts the cake into the oven when it is at 260° and rising. how long will gavin need to leave the cake in the oven? (round your answer to the nearest minute.)

Which if the following types of research is conducted on multiple occasions over time