from math import *


def solve():
    a, b, c, x, y, d = map(int, input().split())

    res0 = a * (d // x + (d % x != 0))
    res4 = res0
    if d // x > 0:
        res4 = a * (d // x)
        rem = d % x
        res4 = res4 + b * min(rem, y)
        rem = rem - y
        res4 = res4 + c * max(0, rem)

    res1 = a
    rem = d - x
    if rem > 0:
        res1 = res1 + b * min(rem, y)
        rem = rem - y
        res1 = res1 + c * max(0, rem)

    res7 = a * (d // x)
    rem = d % x
    res7 = res7 + b * min(rem, (d // x) * y)
    rem = rem - (d // x) * y
    res7 = res7 + c * max(0, rem)

    z = x + y
    e = a + y * b
    res2 = e * (d // z)
    rem = d % z
    res3 = e * (d // z)
    if rem > 0:
        res2 = res2 + a
        res3 = res3 + a * (rem // x + (rem % x != 0))
        rem = rem - x
        if rem > 0:
            res2 = res2 + rem * b

    res5 = res0
    res6 = res0
    if d // z > 0 and d % z > 0:
        res5 = e * (d // z) + c * (d % z)
        res6 = e * (d // z)
        rem = d % z
        p = x - rem % x
        if p < x:
            res6 = res6 - b * min((d // z) * y, p)
            res6 = res6 + a * (rem // x + (rem % x != 0))

    print(
        min(
            res7,
            min(res6,
                min(res5, min(res4, min(res3, min(res0, min(res1, res2))))))))


t = int(input())
for i in range(0, t):
    solve()