Define Becquerel and Curie.

Explanation

Becquerel : 1 disintegration or decay per second is called Becquerel. It is SI unit of activity.
i.e., Becquerel `= ("1 disintegration or decay")/("second")`
Curie : `3.7xx10^(10)` decays per second is called Curie.
1 Curie `= 1Ci=(3.7xx10^(10)" decays")/("second")=3.7xx10^(10)` Bq.