Basically degrees of freedom are related to sample size (n-1). If the df increases, it also stands that the sample size is increasing; the graph of the t-distribution will have skinnier tails, pushing the critical value towards the mean.
The difference is 4hrs because 6-2 is 4
It’s called an equilateral triangle because all sides are even. A triangle equals 180 degrees. So, 60 degrees x 3 sides = 180 degrees
In the usual sense, it has no inverse function. Since it is not an injection (f(0)=f(2)=0), an inverse function would have to map 0 both to 0 and 2, and that’s impossible.
However, if you restrict the domain to [1,+oo> (to make it injective), and the codomain to [-1,+oo> (to make it surjective), then it has an inverse function, given by g(y)=1+sqrt(y+1).