Aradioactive isotope has a half-life of 40 years and a radioactivity level of 4 curies. how many years will it take for the radioactivity level to become 0.25?

1) in the era after world war i and before the great depression, american towns grew rapidly because of

For review 1. in terms of which government is sovereign, differentiate among a unitary system, a confed- eral system, and a federal system of government. 2. to which level of government does the constitution distribute the enumerated po implied powers? concurrent powers? reserved powers? provide several power. 3. what matters fall within the scope of state sovereignty? differentiate among dual federalism, cooperative federalism, centralized federalism, and conflicted federalism. how does the national government use grants-in-aid, mandates, and preemption to direct the policy of state and local governments? 6. what do we mean by intergovernmental relations? why is the term a good description of u.s. federalism today? 7. list several advantages and several disadvantages of a federal system.

In 2004 how many nightly car accidents were there