T=int(input())

for i in range(T):
    n=int(input())
    input_list=list(map(int,input().split()))
    print(max(input_list)-min(input_list), end=" ")
    res=0
    for i in input_list:
        res+=(i-sum(input_list)/n)**2
    res=res/n
    print(f"{res:.3f}")