Solve the Problem $t = 0$ , There Are $29 \mathrm {~g}$

Solve the problem.
-The half-life of a certain radioactive substance is 8 years. Suppose that at time $t = 0$ , there are $29 \mathrm {~g}$ of the substance. Then after t years, the number of grams of the substance remaining will be:
$$N ( t ) = 29 \left( \frac { 1 } { 2 } \right) ^ { t / 16 }$$
How many grams of the substance will remain after 56 years? Round to the nearest hundredth when necessary.

A) $0.64 \mathrm {~g}$
B) $1.28 \mathrm {~g}$
C) $0.32 \mathrm {~g}$
D) $2.56 \mathrm {~g}$