Answer:
I believe it is A
Explanation:
pH = -log[H+] and pOH = -log[OH−].
Answer:
A = 349 g.
Explanation:
Hello there!
In this case, since the radioactive decay kinetic model is based on the first-order kinetics whose integrated rate law is:

We can firstly calculate the rate constant given the half-life as shown below:

Therefore, we can next plug in the rate constant, elapsed time and initial mass of the radioactive to obtain:

Regards!
B. Earth’s tilt
Earth’s tilt exposes different parts of the earth to varying degrees of sunlight throughout the year, causing seasons.