Question

when there is 30% remaining of the radioactive isotope, how much time has passed? select the best option. 1 minute 2 minutes 5 minutes 7 minutes

Explanation:

Step1: Locate 30% on y - axis

Find the 30% mark on the y - axis representing % of unstable isotopes remaining.

Step2: Draw a horizontal line

Draw a horizontal line from the 30% mark on the y - axis until it intersects the curve.

Step3: Draw a vertical line

From the intersection point on the curve, draw a vertical line down to the x - axis.

Step4: Read the time value

Read the value on the x - axis where the vertical line intersects. It is approximately 7 minutes.

Answer:

7 minutes