Answer:
The mass of the radioactive sample after 40 minutes is 12.8 g.
Step-by-step explanation:
The mass of the sample can be found by using the exponential decay equation:
Where:
N(t): is the amount of the sample at time t =?
N₀: is the initial quantity of the sample = 120 g
t = 40 min
λ: is the decay constant = 0.056 min⁻¹
Hence, the mass of the sample after 40 min is:
Therefore, the mass of the radioactive sample after 40 minutes is 12.8 g.
I hope it helps you!
Answer: 89 students remained at school that day.
Step-by-step explanation: If there are 104 students, and 15 are absent, you subtract, therefore, the answer is 89.
Are simply line segments<span> that are equal in length. </span>Congruent<span> means equal.</span>Congruent line segments<span> are usually indicated by drawing the same amount of little tic </span>lines<span> in the middle of the </span>segments, perpendicular to the segments<span>. We indicate a </span>line segment<span> by drawing a</span>line<span> over its two endpoints.</span>
Using the 2nd row it traveled 120 miles in 3 hours
so 120/3 = 40 miles per hour
so distance (d) = 40h
