1. For each of the following congruences, decide whether there is a solution. If not, explain why not. Otherwise, find the general solution in each of the following two forms: - xamodn, where n is an appropriate positive integer and a {0,,n1}. - xa1,,ak1, or akmodm, where m is the modulus of the original congruence and a1,,ak{0,,m1}. (a) 150x18mod252 (b) 224x32mod360 (c) 105x101mod363