Final answer:
The expression 1·7·7·7·7·7 can be written using an exponent as 75, where 7 is the base and 5 is the exponent indicating that 7 is multiplied by itself five times.
Step-by-step explanation:
To write the expression 1·7·7·7·7·7 using an exponent, we observe that the number 7 is being multiplied by itself five times. Multiplication of the same number by itself repeatedly is expressed using exponents. Thus, the expression can be written as 75.
When using exponents, the small raised number, in this case, 5, is called the exponent. It indicates how many times the base number, which is 7, is multiplied by itself. Hence, 7 to the 5th power corresponds to our original expression.