Answer
$5^{1}\times 2^{4}$.
Work Step by Step
When we write a number using exponents, we write the number and then put the exponent above it; this exponent tells us how many times to multiply that number by itself. Here, we see that 5 is multiplied by itself 1 time, and 2 is multiplied by itself 4 times, so we know that the answer should be: $5^{1}\times 2^{4}$.