for _ in range(int(input())):
  a, b, c, x, y, d = map(int, input().split())
  if d <= x:
    print(a)
    continue
  
  tmp_d = d - x
  ans = a
  if tmp_d > y:
    ans += y * b + (tmp_d - y) * c
  else:
    ans += tmp_d * b

  if a <= b * x and a <= c * x:
    k = (d + x - 1) // x
    nans0 = a * k
    remain = d - (k - 1) * x
    nans1 = a * (k - 1)
    if b <= c:
      sum_y = (k - 1) * y
      if remain <= sum_y: nans1 += remain * b
      else: nans1 += sum_y * b + (remain - sum_y) * c
    else:
      if remain <= y: nans1 += remain * b
      else: nans1 += y * b + (remain - y) * c
    ans = min(ans, nans0, nans1)
  elif a >= b * x and b >= c:
    pass
  elif a >= b * x and b <= c and a >= c * x:
    if a + b * y < c * (x + y):
      p = x + y; q = a + b * y
      k = (d + p - 1) // p
      nans0 = (k - 1) * q
      remain = d - (k - 1) * p
      if k > 1:
        ans = min(ans, nans0 + remain * c)
      nans0 += a
      sum_y = (k - 1) * y

      if remain < x:
        nans0 -= min(sum_y, x - remain) * b
      else:
        remain -= x
        nans0 += remain * b
      ans = min(ans, nans0)
  elif b <= c:
    p = x + y; q = a + b * y
    k = (d + p - 1) // p
    nans0 = (k - 1) * q
    remain = d - (k - 1) * p
    if k > 1:
      ans = min(ans, nans0 + remain * c)
    nans0 += a
    sum_y = (k - 1) * y
    if remain < x:
      nans0 -= min(sum_y, x - remain) * b
    else:
      remain -= x
      nans0 += remain * b
    ans = min(ans, nans0)
  else:
    k = (d + x - 1) // x
    nans0 = a * k
    nans1 = a * (k - 1)
    remain = d - (k - 1) * x

    if remain <= y:
      nans1 += remain * b
    else:
      nans1 += y * b + (remain - y) * c
    ans = min(ans, nans0, nans1)
  
  print(ans)

answer.code:1:1: error: expected unqualified-id before ‘for’
    1 | for _ in range(int(input())):
      | ^~~
answer.code:31:18: error: ‘q’ does not name a type
   31 |       p = x + y; q = a + b * y
      |                  ^
answer.code:47:16: error: ‘q’ does not name a type
   47 |     p = x + y; q = a + b * y
      |                ^