MOD = 998244353
def ksm(p, h):
base = p % MOD
res = 1
while h:
if h & 1:
res = res * base % MOD
base = base * base % MOD
h >>= 1
return res
def dec(x, y):
return ((x - y) % MOD + MOD) % MOD
def add(x, y):
return (x + y) % MOD
def mul(x, y):
return x * y % MOD
def sub(x, y):
return ((x - y) % MOD + MOD) % MOD
def pls(x, y):
return ((x + y) % MOD + MOD) % MOD
def mult(x, y):
return x * y % MOD
def solve():
t = int(input())
for _ in range(t):
a, b, c, x, y, d = map(int, input().split())
ans = 0
if d <= x:
print(a)
continue
if x + y >= d:
ans = a + (d - x) * b
else:
ans = a + y * b + (d - x - y) * c
t_val = x + y
cur = (d // t_val) * (a + y * b)
if d >= t_val:
ans = min(ans, cur + (d % t_val) * c)
if d % t_val <= x:
now = (d // t_val) * y
ans = min(ans, cur + a - min(x - d % t_val, now) * b)
else:
ans = min(ans, cur + a + (d % t_val - x) * b)
t_val = x
cur = (d // t_val) * a
if d % t_val == 0:
ans = min(ans, cur)
else:
ans = min(ans, cur + a)
o = d % t_val
now = (d // t_val) * y
if now >= o:
ans = min(ans, cur + o * b)
else:
ans = min(ans, cur + now * b + (o - now) * c)
if y >= o:
ans = min(ans, cur + o * b)
else:
ans = min(ans, cur + y * b + (o - y) * c)
print(ans)
if __name__ == "__main__":
solve()