1. The problem states: If $7^m = t$, find an expression for $7^{m+3}$ in terms of $t$. 2. Recall the exponent rule: $a^{x+y} = a^x \times a^y$. 3. Using this rule, rewrite $7^{m+3}$ as: $$7^{m+3} = 7^m \times 7^3$$ 4. Substitute $7^m = t$: $$7^{m+3} = t \times 7^3$$ 5. Calculate $7^3$: $$7^3 = 7 \times 7 \times 7 = 343$$ 6. Therefore: $$7^{m+3} = 343t$$ This is the expression for $7^{m+3}$ in terms of $t$.