The rate of change of p with respect to t is directly proportional to (10 - t) and inversely proportional to the cube root of p. the differential equation that models this situation is: (see attachment)

Let's go with this slowly.
"rate of change of P with respect to t" means ΔP/Δt or in differential equation, dP/dt.
"directly proportional to (10 - t)" means that it is equal to a constant multiplied with (10-t).
"inversely proportional to the cube root of P" means that the reciprocal of ∛P is multiplied

Following these deductions, the answer would be E.

Element 17 is chlorine it is a group 7 element(halogen) and belongs to period 3 of the periodic table