What is made up of phloem tissue and a cork cambium that protects the stem

The differential equation describing the given situation is dQ/dt = k( 16 - Q )

Explanation:

Given the data in the question;

Initially, the water based solution contains 16 grams of undissolved chemicals;

Assume Q(t) is the amount of dissolved chemical at time L

then the amount of undissolved chemicals at time t is ( 16 - Q)

The rate of change of amount of chemicals dissolved in the solution is proportional to the amount of undissolved chemicals

this means;

dQ/dt ∝ ( 16 - Q)

dQ/dt = k( 16 - Q )

where k is the positive proportionality constant.

Therefore, The differential equation describing the given situation is dQ/dt = k( 16 - Q )