You buy a plastic dart gun and being a clever physics student you decide to do a quick calculation to find its maximum horizontal range. you shoot the gun straight up and it takes 4.1s for the dart to land back at the barrel. what is the macimum horizontal range of your gun?

When a dark gun is shot upwards, the applicable equations are:

y= v0t sin θ − 1/2 gt2 
R = ∆x(t = 2v0 sin θ/g) = v^2 sin(2θ) / g 

when t is 4.1 seconds and θ = 90 degrees, 
we can see in the horizontal range sin(2θ) or sin 180 is equal to zero. Hence the range is equal to zero

The question is kind of confusing. if it's asking how many variations of answers can you give. then do 4^5 for your answer.this would be something like the first question could be a and the 2nd c or first b next c etc. if you can, ask the teacher for a better confirmation of what it's asking. if i'm assuming correctly what it's asking, it's 625 different variations.