n, m, k = gets.split(" ").map(&:to_i)
MOD = 10**9 + 7

def f(n)
  ((n-1)*n*(n+1)/6) %MOD
end

## 二項係数 C(n,k) mod pの計算 ##
# a**b mod p by 繰り返し二乗法
def pow(a,b)
  return 1 if b == 0
  return a*pow(a,b-1)%MOD if b%2 == 1
  return pow(a**2%MOD, b/2)
end

# n! mod p
def fact(n)
  ret = 1
  n.times do |i|
    ret = ret * (i+1) %MOD
  end
  ret
end

# a**(-1) mod p
def inv(a)
  pow(a, MOD-2)%MOD
end

# C(n,k) mod p
def com(n,k)
  (fact(n) * inv(fact(k)))%MOD * inv(fact(n-k)) %MOD
end

puts (m**2 * f(n) + n**2 * f(m)) * com(m*n-2, k-2) %MOD
   