length_list=[]
exam_papers=int(input())
matrix=[[] for _ in range(exam_papers)]
result=[[] for _ in range(exam_papers)]
for i in range(exam_papers):
    length_list=list(input())
    matrix[i]=list(map(int,input().split()))
for i in range(exam_papers):
    jicha=max(matrix[i])-min(matrix[i])
    mean=sum(matrix[i])/(len(matrix[i]))
    variance=0
    for item in matrix[i]:
        variance+=(item-mean)**2/len(matrix[i])
    result[i].append(jicha)
    result[i].append(variance)

for i in result:
    for j in range(2):
        if j == 0:
            print(i[j],end=" ")
        else:
            print(f"{i[j]:.3f}")