Form a polynomial with real coefficients having the given degree and zeroes

Easy

the factorrs of an equation that has the roots, r1,r2,r3,r4 is (x-r1)(x-r2)(x-r3)(x-r4)

also, remember that if it has real coefieints, and a+bi is a root, a-bi is also a root

multiplicities are the number of times the root repeats
so root r1 multiplicity 2 would be (x-r1)^2

so therefor
degree 4
roots are 4+3i and 4-3i and 1 twice
(x-(4-3i))(x-(4+3i))(x-1)²
expanding is a pain
used calculator

not sure what the 'a' in front is

The answer that i got was 8/3

The answer is 225 miles per 4.5 hours. hope this ; )