Asample of tritium-3 decayed to 94.5% of its original amount after a year. (a) what is the half-life of tritium-3? (b) how long would it take the sample to decay to 20% of its original amount?

What is the solution of log2  (3x  -  7)  =  3? 4 5

Lines a and b are parallel. what is the value of x? -5 -10 -35 -55

Atrain leaves little? rock, arkansas, and travels north at 90 kilometers per hour. another train leaves at the same time and travels south at 80 kilometers per hour. how long will it take before they are 680 kilometers? apart?