a) the given expression is
4^3 * 4^4
We would apply one of the laws of exponents which is expressed as
a^b * a^c = a^(b + c)
By comparing the given expression with the law, we have
a = 4
b = 3
c = 4
Thus, we have
4^(3 + 4)
= 4^7
The exponential form of the expression is 4^7