How does blood pressure change when epinephrine is injected<br/>intravenously() A: Rise B: Descent C: First down then up D: Unchanged E: Little change

If a drug with t1/2 3 hours is given intravenously, the blood concentration will drop below 5% of the initial concentration within: A: 6 h B: 9 h C: 15 h D: 25 h E: 30 h