mod = 998244353
def f(r, m, n):
    mq, mr = divmod(m, n)
    rq, rr = divmod(r, n)
    mq %= mod
    mr %= mod
    rq %= mod
    rr %= mod
    return (mq * (r % mod) + mr * rq + min(mr, rr)) % mod


for _ in range(int(input())):
    n, m, l, r = map(int, input().split())
    print((f(r + 1, m + 1, n - 1) - f(l, m + 1, n - 1)) % mod)